Bernoulli Numbers in Arbitrary Precision
Computes the Bernoulli numbers in the desired (binary) precision.
The computation happens via the zeta function and the
formula
B_k = -k ζ(1 - k),
and hence the only non-zero odd Bernoulli number is B_1 = +1/2. (Another tradition defines it, equally sensibly, as -1/2.)
Bernoulli(k, precBits = 128)
k |
non-negative integer vector |
precBits |
the precision in bits desired. |
an mpfr class vector of the same length as
k, with i-th component the k[i]-th Bernoulli number.
Martin Maechler
zeta is used to compute them.
The next version of package gmp is to contain
BernoulliQ(), providing exact Bernoulli numbers as
big rationals (class "bigq").
Bernoulli(0:10)
plot(as.numeric(Bernoulli(0:15)), type = "h")
curve(-x*zeta(1-x), -.2, 15.03, n=300,
main = expression(-x %.% zeta(1-x)))
legend("top", paste(c("even","odd "), "Bernoulli numbers"),
pch=c(1,3), col=2, pt.cex=2, inset=1/64)
abline(h=0,v=0, lty=3, col="gray")
k <- 0:15; k[1] <- 1e-4
points(k, -k*zeta(1-k), col=2, cex=2, pch=1+2*(k%%2))
## They pretty much explode for larger k :
k2 <- 2*(1:120)
plot(k2, abs(as.numeric(Bernoulli(k2))), log = "y")
title("Bernoulli numbers exponential growth")
Bernoulli(10000)# - 9.0494239636 * 10^27677Please choose more modern alternatives, such as Google Chrome or Mozilla Firefox.