OFFSET
0,2
FORMULA
G.f.: 4x/sqrt(1-10x+9x^2) + (1-2x)/(1-x). - Ralf Stephan, Mar 23 2004
Conjecture: (-n+1)*a(n) +(11*n-17)*a(n-1) +(-19*n+43)*a(n-2) +9*(n-3)*a(n-3)=0. - R. J. Mathar, Jun 10 2013
PROG
(PARI) m=matrix(50, 50):for(i=1, 50, m[1, i]=1:m[i, 1]=1):for(i=2, 50, for(k=1, i, x=i-k+1: if(m[x, k]==0, m[x, k]=sum(n=2, k-1, m[x, n])+sum(n=2, x-1, m[n, k])+k+x-1))):for(n=1, 24, print1(m[n, n]", ")) /* Ralf Stephan */
CROSSREFS
KEYWORD
nonn
AUTHOR
Floor van Lamoen, Jul 16 2001
EXTENSIONS
More terms from Ralf Stephan, Mar 23 2004
STATUS
approved