OFFSET
1,2
LINKS
PROG
(PARI)
A064989(n) = { my(f = factor(n)); if((n>1 && f[1, 1]==2), f[1, 2] = 0); for (i=1, #f~, f[i, 1] = precprime(f[i, 1]-1)); factorback(f); };
memoA349358 = Map();
CROSSREFS
KEYWORD
sign
AUTHOR
Antti Karttunen, Nov 17 2021
STATUS
approved