1,1

Table of n, a(n) for n=1..66.

a(n) = A006520(A014105(n)).

(PARI) gpf(n)=local(ps); if(n<2, n, ps=factor(n)[, 1]~; ps[#ps])

vector(80, n, gpf(n*(2*n+1)))

Cf. A006530, A014105, A074399, A093074, A076605.

Sequence in context: A088836 A076565 A286517 * A100029 A099984 A130141

Adjacent sequences: A199420 A199421 A199422 * A199424 A199425 A199426

nonn,easy

Franklin T. Adams-Watters, Nov 06 2011

approved