OFFSET
0,4
LINKS
Index entries for linear recurrences with constant coefficients, signature (0,1,3,3,1).
FORMULA
PROG
(PARI) my(N=40, x='x+O('x^N)); Vec((1+x)/(1-x^2*(1+x)^3))
(PARI) a(n) = sum(k=0, n\2, binomial(3*k+1, n-2*k));
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Aug 12 2024
STATUS
approved