

A013701


Degree of variety K_{2,n}^4.


4



1, 512, 75025, 7174454, 562110290, 39541748736, 2610763825782, 165745451110910, 10262482704258873, 625250747214775916, 37701606156514031251, 2258713106034310399852, 134810129909509070121060
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OFFSET

1,2


COMMENTS

Number of Catalan paths (nonnegative, starting and ending at 0, step +/1) of 6n+8 steps with all values less than or equal to n+1 (see A080934).


LINKS



PROG

(PARI) K(n, q=4)=(2*n+n*q+2*q)!*sum(j=0, q, ((q2*j)*(n+2)+1)/(n+j*(n+2))!/(n+1+(qj)*(n+2))!)


CROSSREFS



KEYWORD

nonn,easy


AUTHOR

Joachim.Rosenthal(AT)nd.edu (Joachim Rosenthal)


STATUS

approved



