

A034269


a(n) = f(n,n+2) where f is given in A034261.


1



0, 1, 11, 76, 435, 2255, 11011, 51688, 236028, 1056210, 4654430, 20266312, 87402185, 374008635, 1590144675, 6724160400, 28303504680, 118665923310, 495820606410, 2065492595400, 8581809094950, 35572994871414, 147149351758926, 607555878211376
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OFFSET

0,3


LINKS



FORMULA

Appears to be a(n) = 4^(n+1)*Pi^(1/2)*GAMMA(n+3/2)/GAMMA(n+5)*(n+1)*n*(n^2+3*n+1).  Mark van Hoeij, Oct 30 2011.


MATHEMATICA

Table[n*(n^2+3*n+1)*Binomial[2*n+2, n]/((n+3)*(n+4)), {n, 0, 20}] (* Vaclav Kotesovec, Oct 27 2012 *)


PROG

(PARI) a(n)=n*(n^2+3*n+1)*binomial(2*n+2, n)/((n+3)*(n+4)); \\ Joerg Arndt, May 04 2013


CROSSREFS



KEYWORD

nonn,easy


AUTHOR



EXTENSIONS



STATUS

approved



