OFFSET
0,2
COMMENTS
3^n may be retrieved as Sum_{k=0..n} (binomial(n,k) mod 2)*A100736(k).
FORMULA
a(n) = Sum_{k=0..n} (-1)^A010060(n-k)*(binomial(n, k) mod 2)*3^k.
PROG
(PARI) a(n)=abs(sum(k=0, n, (-1)^(hammingweight(k)%2)* lift(Mod(binomial(n, k), 2))*3^k)) \\ Jianing Song, Jan 27 2019
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Paul Barry, Dec 06 2004
STATUS
approved