OFFSET
1,2
LINKS
FORMULA
PROG
(PARI)
A019565(n) = {my(j, v); factorback(Mat(vector(if(n, #n=vecextract(binary(n), "-1..1")), j, [prime(j), n[j]])~))}; \\ This function from M. F. Hasler
A193231(n) = { my(x='x); subst(lift(Mod(1, 2)*subst(Pol(binary(n), x), x, 1+x)), x, 2) }; \\ And this from Franklin T. Adams-Watters
vecproduct(v) = { my(m=1); for(i=1, #v, m *= v[i]); m; };
(Scheme, with memoization-macro definec)
CROSSREFS
KEYWORD
nonn,mult
AUTHOR
Antti Karttunen, Oct 31 2017
STATUS
approved