OFFSET
1,3
LINKS
Michel Marcus, Table of n, a(n) for n = 1..10000
EXAMPLE
PROG
(PARI) fk(s, m) = {j = 1; while(denominator(s^j/m) != 1, j++); j; }
rad(n) = factorback(factorint(n)[, 1]);
lista(nn) = {for (n=1, nn, if (denominator(sigma(n)/rad(n)) == 1, k = fk(sigma(n), n); print1(k, ", "); ); ); }
CROSSREFS
KEYWORD
nonn
AUTHOR
Michel Marcus, Nov 06 2015
STATUS
approved