OFFSET
1,2
COMMENTS
All terms are odd.
LINKS
FORMULA
EXAMPLE
a(12) = a(2^2 * 3) = a(prime(1)^2 * prime(2)) = prime(2) * prime(3) = 3 * 5 = 15.
MAPLE
a:= n-> mul(nextprime(i[1]), i=ifactors(n)[2]):
seq(a(n), n=1..100); # Alois P. Heinz, Oct 30 2019
MATHEMATICA
a[1] = 1; a[n_] := Times @@ (NextPrime[#[[1]]] & /@ FactorInteger[n]); Table[a[n], {n, 1, 70}]
PROG
(PARI) a(n) = my(f=factor(n)); prod(k=1, #f~, nextprime(f[k, 1]+1)); \\ Michel Marcus, Oct 30 2019
CROSSREFS
KEYWORD
nonn,mult
AUTHOR
Ilya Gutkovskiy, Oct 30 2019
STATUS
approved