OFFSET
1,2
COMMENTS
Number of Catalan paths (nonnegative, starting and ending at 0, step +/-1) of 4n+4 steps with all values less than or equal to n+1 (see A080934).
LINKS
M. S. Ravi et al., Dynamic pole assignment and Schubert calculus, SIAM J. Control Optimization, 34 (1996), 813-832, esp. p. 825.
PROG
(PARI) K(n, q=2)=(2*n+n*q+2*q)!*sum(j=0, q, ((q-2*j)*(n+2)+1)/(n+j*(n+2))!/(n+1+(q-j)*(n+2))!)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Joachim.Rosenthal(AT)nd.edu (Joachim Rosenthal)
STATUS
approved