BernoulliB
BernoulliB[n] gives the Bernoulli number B_n. BernoulliB[n, x] gives the Bernoulli polynomial B_n(x).
Examples
Bernoulli numbers:
Table[BernoulliB[n], {n, 0, 6}]
(* {1, -1/2, 1/6, 0, -1/30, 0, 1/42} *)Bernoulli polynomial:
BernoulliB[3, x]
(* x^3 - 3*x^2/2 + x/2 *)Please visit the official Wolfram Language Reference for more details.