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 A105631 Row sums of triangle A105629, which is the matrix logarithm of triangle A105623. 1

%I

%S 0,1,5,27,195,1833,21125,286451,4453859,78031153,1520668645,

%T 32631020011,764640901539,19431070911513,532315915981605,

%U 15640217893829891,490640673319698179,16368499360721508833,578693283962999831365

%N Row sums of triangle A105629, which is the matrix logarithm of triangle A105623.

%C A105623 equals the matrix square-root of triangle A105615.

%o (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,sum(k=0,n,L[n+1,k+1])/2))}

%Y Cf. A105629, A105623, A105615.

%K nonn

%O 0,3

%A _Paul D. Hanna_, Apr 16 2005

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Last modified December 2 09:52 EST 2020. Contains 338876 sequences. (Running on oeis4.)