|
|
A365757
|
|
G.f. satisfies A(x) = 1 + x*A(x) / (1 - x^3*A(x)^5).
|
|
2
|
|
|
1, 1, 1, 1, 2, 8, 29, 86, 229, 619, 1836, 5846, 18802, 59356, 185187, 581476, 1855412, 5997965, 19491730, 63395718, 206433172, 674452128, 2213463944, 7293253791, 24098638133, 79791002807, 264698873350, 879945619711, 2931486913728, 9785457123420, 32721317536787
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,5
|
|
LINKS
|
|
|
FORMULA
|
a(n) = Sum_{k=0..floor(n/3)} binomial(n-2*k-1,k) * binomial(n+2*k+1,n-3*k) / (n+2*k+1).
|
|
PROG
|
(PARI) a(n) = sum(k=0, n\3, binomial(n-2*k-1, k)*binomial(n+2*k+1, n-3*k)/(n+2*k+1));
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|