OFFSET
1,4
LINKS
FORMULA
EXAMPLE
a(36) = a(2^2 * 3^2) = a(prime(1)^2 * prime(2)^2) = a(1) * 2 * a(2) * 2 = 4.
MAPLE
a:= proc(n) option remember;
mul(a(numtheory[pi](i[1]))*i[2], i=ifactors(n)[2])
end:
seq(a(n), n=1..120); # Alois P. Heinz, Mar 13 2020
MATHEMATICA
a[1] = 1; a[n_] := a[n] = Times @@ (a[PrimePi[#[[1]]]] #[[2]] & /@ FactorInteger[n]); Table[a[n], {n, 1, 100}]
CROSSREFS
KEYWORD
nonn,mult
AUTHOR
Ilya Gutkovskiy, Mar 13 2020
STATUS
approved