OFFSET
1,3
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..2000
FORMULA
a(n) * A193267(n) = n.
MAPLE
MATHEMATICA
a[n_]:=If[OddQ[n], 1, Denominator[BernoulliB[n]/n]/Denominator[BernoulliB[n]]]; Table[n/a[n], {n, 1, 100}] (* Vincenzo Librandi, Mar 12 2018 *)
PROG
(Julia)
using Nemo
function A300330(n) P = 1
for (p, e) in factor(ZZ(n))
! divisible(ZZ(n), p - 1) && (P *= p^e) end
P end
[A300330(n) for n in 1:72] |> println
(Magma) [n/(Denominator(Bernoulli(n)/n)/Denominator(Bernoulli(n))): n in [1..100]]; // Vincenzo Librandi, Mar 12 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
Peter Luschny, Mar 12 2018
STATUS
approved