Table of contents: Definitions - Main formulas - Integral representations - Hypergeometric representations - Symmetry - Integer parameters - Recurrence relations
| Fungrim symbol | Notation | Short description |
|---|---|---|
| BetaFunction | B(a,b) | Beta function |
Entry(ID("1c46fa"),
SymbolDefinition(BetaFunction, BetaFunction(a, b), "Beta function"))| Fungrim symbol | Notation | Short description |
|---|---|---|
| IncompleteBeta | Bx(a,b) | Incomplete beta function |
Entry(ID("795fe5"),
SymbolDefinition(IncompleteBeta, IncompleteBeta(x, a, b), "Incomplete beta function"))| Fungrim symbol | Notation | Short description |
|---|---|---|
| IncompleteBetaRegularized | Ix(a,b) | Regularized incomplete beta function |
Entry(ID("6bd011"),
SymbolDefinition(IncompleteBetaRegularized, IncompleteBetaRegularized(x, a, b), "Regularized incomplete beta function"))\mathrm{B}\!\left(a, b\right) = \frac{\Gamma(a) \Gamma(b)}{\Gamma\!\left(a + b\right)}
a \in \mathbb{C} \setminus \{0, -1, \ldots\} \;\mathbin{\operatorname{and}}\; b \in \mathbb{C} \setminus \{0, -1, \ldots\}| Fungrim symbol | Notation | Short description |
|---|---|---|
| BetaFunction | B(a,b) | Beta function |
| Gamma | Γ(z) | Gamma function |
| CC | C | Complex numbers |
| ZZLessEqual | Z≤n | Integers less than or equal to n |
Entry(ID("888581"),
Formula(Equal(BetaFunction(a, b), Div(Mul(Gamma(a), Gamma(b)), Gamma(Add(a, b))))),
Variables(a, b),
Assumptions(And(Element(a, SetMinus(CC, ZZLessEqual(0))), Element(b, SetMinus(CC, ZZLessEqual(0))))))I_{x}\!\left(a, b\right) = \frac{\mathrm{B}_{x}\!\left(a, b\right)}{\mathrm{B}\!\left(a, b\right)}
x \in \mathbb{C} \;\mathbin{\operatorname{and}}\; a \in \mathbb{C} \setminus \{0, -1, \ldots\} \;\mathbin{\operatorname{and}}\; b \in \mathbb{C} \setminus \{0, -1, \ldots\} \;\mathbin{\operatorname{and}}\; a + b \notin \{0, -1, \ldots\}| Fungrim symbol | Notation | Short description |
|---|---|---|
| IncompleteBetaRegularized | Ix(a,b) | Regularized incomplete beta function |
| IncompleteBeta | Bx(a,b) | Incomplete beta function |
| BetaFunction | B(a,b) | Beta function |
| CC | C | Complex numbers |
| ZZLessEqual | Z≤n | Integers less than or equal to n |
Entry(ID("c92da4"),
Formula(Equal(IncompleteBetaRegularized(x, a, b), Div(IncompleteBeta(x, a, b), BetaFunction(a, b)))),
Variables(x, a, b),
Assumptions(And(Element(x, CC), Element(a, SetMinus(CC, ZZLessEqual(0))), Element(b, SetMinus(CC, ZZLessEqual(0))), NotElement(Add(a, b), ZZLessEqual(0)))))\mathrm{B}_{0}\!\left(a, b\right) = 0
a \in \mathbb{C} \setminus \{0, -1, \ldots\} \;\mathbin{\operatorname{and}}\; b \in \mathbb{C} \setminus \{0, -1, \ldots\}| Fungrim symbol | Notation | Short description |
|---|---|---|
| IncompleteBeta | Bx(a,b) | Incomplete beta function |
| CC | C | Complex numbers |
| ZZLessEqual | Z≤n | Integers less than or equal to n |
Entry(ID("ba7baf"),
Formula(Equal(IncompleteBeta(0, a, b), 0)),
Variables(a, b),
Assumptions(And(Element(a, SetMinus(CC, ZZLessEqual(0))), Element(b, SetMinus(CC, ZZLessEqual(0))))))\mathrm{B}_{1}\!\left(a, b\right) = \mathrm{B}\!\left(a, b\right)
a \in \mathbb{C} \setminus \{0, -1, \ldots\} \;\mathbin{\operatorname{and}}\; b \in \mathbb{C} \setminus \{0, -1, \ldots\}| Fungrim symbol | Notation | Short description |
|---|---|---|
| IncompleteBeta | Bx(a,b) | Incomplete beta function |
| BetaFunction | B(a,b) | Beta function |
| CC | C | Complex numbers |
| ZZLessEqual | Z≤n | Integers less than or equal to n |
Entry(ID("3141e4"),
Formula(Equal(IncompleteBeta(1, a, b), BetaFunction(a, b))),
Variables(a, b),
Assumptions(And(Element(a, SetMinus(CC, ZZLessEqual(0))), Element(b, SetMinus(CC, ZZLessEqual(0))))))I_{0}\!\left(a, b\right) = 0
x \in \mathbb{C} \;\mathbin{\operatorname{and}}\; a \in \mathbb{C} \setminus \{0, -1, \ldots\} \;\mathbin{\operatorname{and}}\; b \in \mathbb{C} \setminus \{0, -1, \ldots\} \;\mathbin{\operatorname{and}}\; a + b \notin \{0, -1, \ldots\}| Fungrim symbol | Notation | Short description |
|---|---|---|
| IncompleteBetaRegularized | Ix(a,b) | Regularized incomplete beta function |
| CC | C | Complex numbers |
| ZZLessEqual | Z≤n | Integers less than or equal to n |
Entry(ID("ff613a"),
Formula(Equal(IncompleteBetaRegularized(0, a, b), 0)),
Variables(x, a, b),
Assumptions(And(Element(x, CC), Element(a, SetMinus(CC, ZZLessEqual(0))), Element(b, SetMinus(CC, ZZLessEqual(0))), NotElement(Add(a, b), ZZLessEqual(0)))))I_{1}\!\left(a, b\right) = 1
x \in \mathbb{C} \;\mathbin{\operatorname{and}}\; a \in \mathbb{C} \setminus \{0, -1, \ldots\} \;\mathbin{\operatorname{and}}\; b \in \mathbb{C} \setminus \{0, -1, \ldots\} \;\mathbin{\operatorname{and}}\; a + b \notin \{0, -1, \ldots\}| Fungrim symbol | Notation | Short description |
|---|---|---|
| IncompleteBetaRegularized | Ix(a,b) | Regularized incomplete beta function |
| CC | C | Complex numbers |
| ZZLessEqual | Z≤n | Integers less than or equal to n |
Entry(ID("6bcfa6"),
Formula(Equal(IncompleteBetaRegularized(1, a, b), 1)),
Variables(x, a, b),
Assumptions(And(Element(x, CC), Element(a, SetMinus(CC, ZZLessEqual(0))), Element(b, SetMinus(CC, ZZLessEqual(0))), NotElement(Add(a, b), ZZLessEqual(0)))))\mathrm{B}\!\left(a, b\right) = \int_{0}^{1} {t}^{a - 1} {\left(1 - t\right)}^{b - 1} \, dt
a \in \mathbb{C} \;\mathbin{\operatorname{and}}\; b \in \mathbb{C} \;\mathbin{\operatorname{and}}\; \operatorname{Re}(a) > 0 \;\mathbin{\operatorname{and}}\; \operatorname{Re}(b) > 0| Fungrim symbol | Notation | Short description |
|---|---|---|
| BetaFunction | B(a,b) | Beta function |
| Integral | ∫abf(x)dx | Integral |
| Pow | ab | Power |
| CC | C | Complex numbers |
| Re | Re(z) | Real part |
Entry(ID("542cf7"),
Formula(Equal(BetaFunction(a, b), Integral(Mul(Pow(t, Sub(a, 1)), Pow(Sub(1, t), Sub(b, 1))), For(t, 0, 1)))),
Variables(a, b),
Assumptions(And(Element(a, CC), Element(b, CC), Greater(Re(a), 0), Greater(Re(b), 0))))\mathrm{B}\!\left(a, b\right) = 2 \int_{0}^{\pi / 2} \sin^{2 a - 1}\!\left(t\right) \cos^{2 b - 1}\!\left(t\right) \, dt
a \in \mathbb{C} \;\mathbin{\operatorname{and}}\; b \in \mathbb{C} \;\mathbin{\operatorname{and}}\; \operatorname{Re}(a) > 0 \;\mathbin{\operatorname{and}}\; \operatorname{Re}(b) > 0| Fungrim symbol | Notation | Short description |
|---|---|---|
| BetaFunction | B(a,b) | Beta function |
| Integral | ∫abf(x)dx | Integral |
| Pow | ab | Power |
| Sin | sin(z) | Sine |
| Cos | cos(z) | Cosine |
| Pi | π | The constant pi (3.14...) |
| CC | C | Complex numbers |
| Re | Re(z) | Real part |
Entry(ID("48910b"),
Formula(Equal(BetaFunction(a, b), Mul(2, Integral(Mul(Pow(Sin(t), Sub(Mul(2, a), 1)), Pow(Cos(t), Sub(Mul(2, b), 1))), For(t, 0, Div(Pi, 2)))))),
Variables(a, b),
Assumptions(And(Element(a, CC), Element(b, CC), Greater(Re(a), 0), Greater(Re(b), 0))))\mathrm{B}_{x}\!\left(a, b\right) = \int_{0}^{x} {t}^{a - 1} {\left(1 - t\right)}^{b - 1} \, dt
x \in \left[0, 1\right] \;\mathbin{\operatorname{and}}\; a \in \mathbb{C} \;\mathbin{\operatorname{and}}\; b \in \mathbb{C} \;\mathbin{\operatorname{and}}\; \operatorname{Re}(a) > 0 \;\mathbin{\operatorname{and}}\; \operatorname{Re}(b) > 0| Fungrim symbol | Notation | Short description |
|---|---|---|
| IncompleteBeta | Bx(a,b) | Incomplete beta function |
| Integral | ∫abf(x)dx | Integral |
| Pow | ab | Power |
| ClosedInterval | [a,b] | Closed interval |
| CC | C | Complex numbers |
| Re | Re(z) | Real part |
Entry(ID("3e08b6"),
Formula(Equal(IncompleteBeta(x, a, b), Integral(Mul(Pow(t, Sub(a, 1)), Pow(Sub(1, t), Sub(b, 1))), For(t, 0, x)))),
Variables(x, a, b),
Assumptions(And(Element(x, ClosedInterval(0, 1)), Element(a, CC), Element(b, CC), Greater(Re(a), 0), Greater(Re(b), 0))))I_{x}\!\left(a, b\right) = \frac{1}{\mathrm{B}\!\left(a, b\right)} \int_{0}^{x} {t}^{a - 1} {\left(1 - t\right)}^{b - 1} \, dt
x \in \left[0, 1\right] \;\mathbin{\operatorname{and}}\; a \in \mathbb{C} \;\mathbin{\operatorname{and}}\; b \in \mathbb{C} \;\mathbin{\operatorname{and}}\; \operatorname{Re}(a) > 0 \;\mathbin{\operatorname{and}}\; \operatorname{Re}(b) > 0| Fungrim symbol | Notation | Short description |
|---|---|---|
| IncompleteBetaRegularized | Ix(a,b) | Regularized incomplete beta function |
| BetaFunction | B(a,b) | Beta function |
| Integral | ∫abf(x)dx | Integral |
| Pow | ab | Power |
| ClosedInterval | [a,b] | Closed interval |
| CC | C | Complex numbers |
| Re | Re(z) | Real part |
Entry(ID("a1941b"),
Formula(Equal(IncompleteBetaRegularized(x, a, b), Mul(Div(1, BetaFunction(a, b)), Integral(Mul(Pow(t, Sub(a, 1)), Pow(Sub(1, t), Sub(b, 1))), For(t, 0, x))))),
Variables(x, a, b),
Assumptions(And(Element(x, ClosedInterval(0, 1)), Element(a, CC), Element(b, CC), Greater(Re(a), 0), Greater(Re(b), 0))))\mathrm{B}_{x}\!\left(a, b\right) = \frac{{x}^{a}}{a} \,{}_2F_1\!\left(a, 1 - b, a + 1, x\right)
a \in \mathbb{C} \setminus \{0, -1, \ldots\} \;\mathbin{\operatorname{and}}\; b \in \mathbb{C} \;\mathbin{\operatorname{and}}\; x \in \mathbb{C} \setminus \left\{1\right\} \;\mathbin{\operatorname{and}}\; \left(x \ne 0 \;\mathbin{\operatorname{or}}\; \operatorname{Re}(a) > 0\right)| Fungrim symbol | Notation | Short description |
|---|---|---|
| IncompleteBeta | Bx(a,b) | Incomplete beta function |
| Pow | ab | Power |
| Hypergeometric2F1 | 2F1(a,b,c,z) | Gauss hypergeometric function |
| CC | C | Complex numbers |
| ZZLessEqual | Z≤n | Integers less than or equal to n |
| Re | Re(z) | Real part |
Entry(ID("5ec9c0"),
Formula(Equal(IncompleteBeta(x, a, b), Mul(Div(Pow(x, a), a), Hypergeometric2F1(a, Sub(1, b), Add(a, 1), x)))),
Variables(x, a, b),
Assumptions(And(Element(a, SetMinus(CC, ZZLessEqual(0))), Element(b, CC), Element(x, SetMinus(CC, Set(1))), Or(NotEqual(x, 0), Greater(Re(a), 0)))))\mathrm{B}\!\left(a, b\right) = \mathrm{B}\!\left(b, a\right)
a \in \mathbb{C} \setminus \{0, -1, \ldots\} \;\mathbin{\operatorname{and}}\; b \in \mathbb{C} \setminus \{0, -1, \ldots\}| Fungrim symbol | Notation | Short description |
|---|---|---|
| BetaFunction | B(a,b) | Beta function |
| CC | C | Complex numbers |
| ZZLessEqual | Z≤n | Integers less than or equal to n |
Entry(ID("cc2ebb"),
Formula(Equal(BetaFunction(a, b), BetaFunction(b, a))),
Variables(a, b),
Assumptions(And(Element(a, SetMinus(CC, ZZLessEqual(0))), Element(b, SetMinus(CC, ZZLessEqual(0))))))I_{x}\!\left(a, b\right) = 1 - I_{1 - x}\!\left(b, a\right)
x \in \mathbb{C} \;\mathbin{\operatorname{and}}\; a \in \mathbb{C} \setminus \{0, -1, \ldots\} \;\mathbin{\operatorname{and}}\; b \in \mathbb{C} \setminus \{0, -1, \ldots\} \;\mathbin{\operatorname{and}}\; a + b \notin \{0, -1, \ldots\}| Fungrim symbol | Notation | Short description |
|---|---|---|
| IncompleteBetaRegularized | Ix(a,b) | Regularized incomplete beta function |
| CC | C | Complex numbers |
| ZZLessEqual | Z≤n | Integers less than or equal to n |
Entry(ID("315b3d"),
Formula(Equal(IncompleteBetaRegularized(x, a, b), Sub(1, IncompleteBetaRegularized(Sub(1, x), b, a)))),
Variables(a, b, x),
Assumptions(And(Element(x, CC), Element(a, SetMinus(CC, ZZLessEqual(0))), Element(b, SetMinus(CC, ZZLessEqual(0))), NotElement(Add(a, b), ZZLessEqual(0)))))\mathrm{B}\!\left(a, b\right) \mathrm{B}\!\left(a + b, c\right) = \mathrm{B}\!\left(b, c\right) \mathrm{B}\!\left(a, b + c\right)
a \in \mathbb{C} \setminus \{0, -1, \ldots\} \;\mathbin{\operatorname{and}}\; b \in \mathbb{C} \setminus \{0, -1, \ldots\} \;\mathbin{\operatorname{and}}\; c \in \mathbb{C} \setminus \{0, -1, \ldots\} \;\mathbin{\operatorname{and}}\; a + b \notin \{0, -1, \ldots\} \;\mathbin{\operatorname{and}}\; b + c \notin \{0, -1, \ldots\}| Fungrim symbol | Notation | Short description |
|---|---|---|
| BetaFunction | B(a,b) | Beta function |
| CC | C | Complex numbers |
| ZZLessEqual | Z≤n | Integers less than or equal to n |
Entry(ID("fd0e48"),
Formula(Equal(Mul(BetaFunction(a, b), BetaFunction(Add(a, b), c)), Mul(BetaFunction(b, c), BetaFunction(a, Add(b, c))))),
Variables(a, b, c),
Assumptions(And(Element(a, SetMinus(CC, ZZLessEqual(0))), Element(b, SetMinus(CC, ZZLessEqual(0))), Element(c, SetMinus(CC, ZZLessEqual(0))), NotElement(Add(a, b), ZZLessEqual(0)), NotElement(Add(b, c), ZZLessEqual(0)))))\mathrm{B}\!\left(m, n\right) = \frac{\left(m - 1\right)! \left(n - 1\right)!}{\left(m + n - 1\right)!}
m \in \mathbb{Z}_{\ge 1} \;\mathbin{\operatorname{and}}\; n \in \mathbb{Z}_{\ge 1}| Fungrim symbol | Notation | Short description |
|---|---|---|
| BetaFunction | B(a,b) | Beta function |
| Factorial | n! | Factorial |
| ZZGreaterEqual | Z≥n | Integers greater than or equal to n |
Entry(ID("082a69"),
Formula(Equal(BetaFunction(m, n), Div(Mul(Factorial(Sub(m, 1)), Factorial(Sub(n, 1))), Factorial(Sub(Add(m, n), 1))))),
Variables(m, n),
Assumptions(And(Element(m, ZZGreaterEqual(1)), Element(n, ZZGreaterEqual(1)))))\mathrm{B}\!\left(m, n\right) = \frac{1}{m {m + n - 1 \choose m}}
m \in \mathbb{Z}_{\ge 1} \;\mathbin{\operatorname{and}}\; n \in \mathbb{Z}_{\ge 1}| Fungrim symbol | Notation | Short description |
|---|---|---|
| BetaFunction | B(a,b) | Beta function |
| Binomial | (kn) | Binomial coefficient |
| ZZGreaterEqual | Z≥n | Integers greater than or equal to n |
Entry(ID("bb4f41"),
Formula(Equal(BetaFunction(m, n), Div(1, Mul(m, Binomial(Sub(Add(m, n), 1), m))))),
Variables(m, n),
Assumptions(And(Element(m, ZZGreaterEqual(1)), Element(n, ZZGreaterEqual(1)))))\mathrm{B}\!\left(n, b\right) = \begin{cases} {\tilde \infty}, & -b \in \{0, 1, \ldots, n - 1\}\\\frac{1}{n {n + b - 1 \choose n}}, & \text{otherwise}\\ \end{cases}
n \in \mathbb{Z}_{\ge 1} \;\mathbin{\operatorname{and}}\; b \in \mathbb{C}| Fungrim symbol | Notation | Short description |
|---|---|---|
| BetaFunction | B(a,b) | Beta function |
| UnsignedInfinity | ∞~ | Unsigned infinity |
| Range | {a,a+1,…,b} | Integers between given endpoints |
| Binomial | (kn) | Binomial coefficient |
| ZZGreaterEqual | Z≥n | Integers greater than or equal to n |
| CC | C | Complex numbers |
Entry(ID("72db94"),
Formula(Equal(BetaFunction(n, b), Cases(Tuple(UnsignedInfinity, Element(Neg(b), Range(0, Sub(n, 1)))), Tuple(Div(1, Mul(n, Binomial(Sub(Add(n, b), 1), n))), Otherwise)))),
Variables(n, b),
Assumptions(And(Element(n, ZZGreaterEqual(1)), Element(b, CC))))\mathrm{B}\!\left(-n, b\right) = \begin{cases} \frac{{\left(-1\right)}^{b}}{b {n \choose b}}, & b \in \{1, 2, \ldots, n\}\\{\tilde \infty}, & \text{otherwise}\\ \end{cases}
n \in \mathbb{Z}_{\ge 0} \;\mathbin{\operatorname{and}}\; b \in \mathbb{C}| Fungrim symbol | Notation | Short description |
|---|---|---|
| BetaFunction | B(a,b) | Beta function |
| Pow | ab | Power |
| Binomial | (kn) | Binomial coefficient |
| Range | {a,a+1,…,b} | Integers between given endpoints |
| UnsignedInfinity | ∞~ | Unsigned infinity |
| ZZGreaterEqual | Z≥n | Integers greater than or equal to n |
| CC | C | Complex numbers |
Entry(ID("a7dbf6"),
Formula(Equal(BetaFunction(Neg(n), b), Cases(Tuple(Div(Pow(-1, b), Mul(b, Binomial(n, b))), Element(b, Range(1, n))), Tuple(UnsignedInfinity, Otherwise)))),
Variables(n, b),
Assumptions(And(Element(n, ZZGreaterEqual(0)), Element(b, CC))))\mathop{\operatorname{res}}\limits_{z=a} \mathrm{B}\!\left(z, b\right) = \begin{cases} {n - b \choose n}, & n \in \mathbb{Z}_{\ge 0}\\0, & \text{otherwise}\\ \end{cases}\; \text{ where } n = -a
a \in \mathbb{C} \;\mathbin{\operatorname{and}}\; b \in \mathbb{C} \setminus \{0, -1, \ldots\}| Fungrim symbol | Notation | Short description |
|---|---|---|
| Residue | z=cresf(z) | Complex residue |
| BetaFunction | B(a,b) | Beta function |
| Binomial | (kn) | Binomial coefficient |
| ZZGreaterEqual | Z≥n | Integers greater than or equal to n |
| CC | C | Complex numbers |
| ZZLessEqual | Z≤n | Integers less than or equal to n |
Entry(ID("1f72e9"),
Formula(Equal(Residue(BetaFunction(z, b), For(z, a)), Where(Cases(Tuple(Binomial(Sub(n, b), n), Element(n, ZZGreaterEqual(0))), Tuple(0, Otherwise)), Equal(n, Neg(a))))),
Variables(a, b),
Assumptions(And(Element(a, CC), Element(b, SetMinus(CC, ZZLessEqual(0))))))\left(a + b\right) \mathrm{B}\!\left(a + 1, b\right) = a \mathrm{B}\!\left(a, b\right)
a \in \mathbb{C} \setminus \{0, -1, \ldots\} \;\mathbin{\operatorname{and}}\; b \in \mathbb{C} \setminus \{0, -1, \ldots\}| Fungrim symbol | Notation | Short description |
|---|---|---|
| BetaFunction | B(a,b) | Beta function |
| CC | C | Complex numbers |
| ZZLessEqual | Z≤n | Integers less than or equal to n |
Entry(ID("bdea17"),
Formula(Equal(Mul(Add(a, b), BetaFunction(Add(a, 1), b)), Mul(a, BetaFunction(a, b)))),
Variables(a, b),
Assumptions(And(Element(a, SetMinus(CC, ZZLessEqual(0))), Element(b, SetMinus(CC, ZZLessEqual(0))))))\mathrm{B}\!\left(a, b\right) = \mathrm{B}\!\left(a + 1, b\right) + \mathrm{B}\!\left(a, b + 1\right)
a \in \mathbb{C} \setminus \{0, -1, \ldots\} \;\mathbin{\operatorname{and}}\; b \in \mathbb{C} \setminus \{0, -1, \ldots\}| Fungrim symbol | Notation | Short description |
|---|---|---|
| BetaFunction | B(a,b) | Beta function |
| CC | C | Complex numbers |
| ZZLessEqual | Z≤n | Integers less than or equal to n |
Entry(ID("e9f966"),
Formula(Equal(BetaFunction(a, b), Add(BetaFunction(Add(a, 1), b), BetaFunction(a, Add(b, 1))))),
Variables(a, b),
Assumptions(And(Element(a, SetMinus(CC, ZZLessEqual(0))), Element(b, SetMinus(CC, ZZLessEqual(0))))))Copyright (C) Fredrik Johansson and contributors. Fungrim is provided under the MIT license. The source code is on GitHub.
2021-03-15 19:12:00.328586 UTC