OFFSET
1
LINKS
FORMULA
a(n) = abs(A091219(n)).
PROG
(PARI) A304109(n) = { my(fm=factor(Pol(binary(n))*Mod(1, 2))); for(k=1, #fm~, if(fm[k, 2] > 1, return(0))); (1); };
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, May 13 2018
STATUS
approved