login
A366407
G.f. A(x) satisfies A(x) = (1 + x / A(x)^(9/2)) / (1 - x).
7
1, 2, -7, 74, -820, 10196, -134785, 1860668, -26508457, 386843804, -5753126477, 86878155652, -1328593620692, 20533664196478, -320220157730975, 5032648114664896, -79629405527982623, 1267425784159379572, -20279086501234998596, 325989622456860054852
OFFSET
0,2
FORMULA
a(n) = (-1)^(n-1) * Sum_{k=0..n} binomial(11*k/2-1,k) * binomial(9*k/2-1,n-k) / (11*k/2-1).
PROG
(PARI) a(n) = (-1)^(n-1)*sum(k=0, n, binomial(11*k/2-1, k)*binomial(9*k/2-1, n-k)/(11*k/2-1));
KEYWORD
sign
AUTHOR
Seiichi Manyama, Oct 09 2023
STATUS
approved