OFFSET
1,1
LINKS
FORMULA
A111775(n) = 0 if and only if a(n) = 0.
A111787(n) = 0 if and only if a(n) = 0.
a(n) = 1 for n in A111774. - Michel Marcus, Aug 28 2017
PROG
(PARI) {a(n) = n>0 && !isprime(n) && n != 2^valuation(n, 2)}
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Michael Somos, Dec 16 2011
STATUS
approved