A107725 Column 0 of A107724, which is the matrix logarithm of triangle A107719.

0, 1, 4, 31, 343, 4855, 83209, 1670743, 38436673, 996825703, 28778874481, 915636860023, 31837734460129, 1201360385000071, 48899006799783889, 2135779996980897175, 99646497213608842561, 4946194601237466540967

Offset: 0

Author

Paul D. Hanna, May 30 2005

Keywords

• nonn

Crossrefs

Cf. A107717, A107719, A107724.

Programs

PARI

{a(n)=local(L,M=matrix(n+1,n+1,m,j,if(m>=j,if(m==j,1,if(m==j+1,-3*j, polcoeff(1/sum(i=0,m-j,prod(r=0,i-1,3*r+1)*x^i)+O(x^m),m-j)))))^-1); L=sum(i=1,#M,(-1)^(i-1)*(M-M^0)^i/i);return(if(n<0,0,L[n+1,1]/3))}