OFFSET
1,4
FORMULA
a(n) = T(n,1), T(n,m) = Sum_{k=1..n-m} T(n-m,k)*m*binomial(2*k+m-1,k+m-1)/(k+m)-binomial(n-1,k+m-2)*T(k+m-1,m), n>m, T(n,n)=1.
PROG
(Maxima)
array(BB, 100, 100);
fillarray (BB, makelist (-1, i, 1, 1000));
T(n, m):=if BB[n, m]=-1 then BB[n, m]:(if n=m then 1 else sum(T(n-m, k)*m*binomial(2*k+m-1, k+m-1)/(k+m)-binomial(n-1, k+m-2)*T(k+m-1, m), k, 1, n-m)) else BB[n, m];
makelist(T(n, 1), n, 1, 27);
CROSSREFS
KEYWORD
sign
AUTHOR
Vladimir Kruchinin, Dec 04 2011
STATUS
approved