login
A366050
Expansion of (1/x) * Series_Reversion( x*(1-x)^4/(1-x+x^2) ).
2
1, 3, 16, 104, 750, 5769, 46373, 384885, 3273118, 28372354, 249762585, 2226782078, 20065651123, 182457467898, 1672073116401, 15427427247088, 143191280370438, 1336062703751262, 12524930325385008, 117910257665608080, 1114233543986585741
OFFSET
0,2
FORMULA
a(n) = (1/(n+1)) * Sum_{k=0..floor(n/2)} binomial(n+1,k) * binomial(4*n-k+2,n-2*k).
PROG
(PARI) a(n) = sum(k=0, n\2, binomial(n+1, k)*binomial(4*n-k+2, n-2*k))/(n+1);
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Sep 27 2023
STATUS
approved