OFFSET
0,3
LINKS
Index entries for linear recurrences with constant coefficients, signature (-1,1,3,3,1).
FORMULA
a(n) = -a(n-1) + a(n-2) + 3*a(n-3) + 3*a(n-4) + a(n-5).
a(n) = Sum_{k=0..floor(n/2)} binomial(2*k-1,n-2*k).
PROG
(PARI) my(N=50, x='x+O('x^N)); Vec(1/((1+x)*(1-x^2*(1+x)^2)))
(PARI) a(n) = sum(k=0, n\2, binomial(2*k-1, n-2*k));
CROSSREFS
KEYWORD
sign,easy
AUTHOR
Seiichi Manyama, Aug 13 2024
STATUS
approved