[Next][Prev] [Right] [Left] [Up] [Index] [Root]

Combinatorial Functions

Factorial(n) : RngIntElt -> RngIntElt
The factorial n! for non-negative small integer n.
NumberOfPermutations(n, k) : RngIntElt, RngIntElt -> RngIntElt
The number of permutations of n distinct objects taken k at a time.
Binomial(n, r) : RngIntElt, RngIntElt -> RngIntElt
The binomial coefficient n choose r.
Multinomial(n, [a_1, ... a_n]) : RngIntElt, [RngIntElt] -> RngIntElt
Given a sequence Q = [r_1, ..., r_k] of positive integers such that n = r_1 + ... + r_k, return the multinomial coefficient n choose r_1, ..., r_k.
Fibonacci(n) : RngIntElt -> RngIntElt
Given an integer n, this function returns the n-th Fibonacci number F_n, which can be defined via the recursion F_0 = 0, F_1 = 1 and F_n = F_(n - 1) + F_(n - 2) for all integers n. Note that n is allowed to be negative, and that F_(-n) = ( - 1)^(n + 1) F_n.
Lucas(n) : RngIntElt -> RngIntElt
Given an integer n, this function returns the n-th Lucas number L_n, which can be defined via the recursion L_0 = 2, L_1 = 1 and L_n = L_(n - 1) + L_(n - 2) for all integers n. Note that n is allowed to be negative, and that L_(-n) = ( - 1)^(n)L_n.
GeneralizedFibonacciNumber(g0, g1, n) : RngIntElt, RngIntElt, RngIntElt -> RngIntElt
The nth member of the generalized Fibonacci sequence defined by G_0 = g_0, G_1 = g_1 and G_n = G_(n - 1) + G_(n - 2) for all integers n. Note that n is allowed to be negative. The Fibonacci and Lucas numbers are special cases where (g_0, g_1) = (0, 1) or (2, 1) respectively.
StirlingFirst(m, n) : RngIntElt, RngIntElt -> RngIntElt
The Stirling number of the first type, [(m atop n)], where m and n are non-negative integers.
StirlingSecond(m, n) : RngIntElt, RngIntElt -> RngIntElt
The Stirling number of the second type, {(m atop n)}, where m and n are non-negative integers.
EulerianNumber(n, r) : RngIntElt, RngIntElt -> RngIntElt
The number E(n, r) of permutations p of {1, ..., n} having exactly k ascents (i.e., places where p_i < p_(i + 1))
HarmonicNumber(n) : RngIntElt -> RngIntElt
The nth harmonic number H_n = Sigma_(i=1)^n (1/i).
BernoulliNumber(n) : RngIntElt -> RngIntElt
Returns the nth Bernoulli number B_n as a rational number.
BernoulliApproximation(n) : RngIntElt -> FldPrElt
Returns a real approximation to the nth Bernoulli number B_n.
BernoulliPolynomial(n) : RngIntElt -> RngUPolElt
The nth Bernoulli polynomial B_n(x) = sum_(k=0)^n (n choose k) B_k x^(n - k) where B_n is the nth Bernoulli number.
 [Next][Prev] [Right] [Left] [Up] [Index] [Root]