A105630 Column 0 of triangle A105629, which is the matrix logarithm of triangle A105623.

0, 1, 3, 17, 135, 1353, 16251, 226857, 3605775, 64288209, 1270969971, 27603549057, 653517822615, 16755529944729, 462601460800491, 13685474246611737, 431948067953729055, 14489465807596684449, 514794897939436455651

Offset: 0

Author

Paul D. Hanna, Apr 16 2005

Keywords

• nonn

Comments

A105623 equals the matrix square-root of triangle A105615.

Crossrefs

Cf. A105629, A105623, A105615.

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,-2*j, polcoeff(1/sum(i=0,m-j,(2*i)!/i!/2^i*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]/2))}