OFFSET
1,1
COMMENTS
EXAMPLE
PROG
(PARI) f(n) = sumdivmult(n, d, d*moebius(d)); \\ from A023900
lista(nn) = {va = []; for (n=2, nn, x = f(n); if ((x = f(n)) < 0, if (! isprime(n) && !vecsearch(va, x), print1(n, ", ")); va = vecsort(concat(va, x), , 8); ); ); } \\ Michel Marcus, Mar 14 2018
CROSSREFS
KEYWORD
nonn
AUTHOR
Torlach Rush, Mar 12 2018
STATUS
approved