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A104991 Row sums of triangle A104990, which equals the matrix cube of triangle A104980. 1

%I

%S 1,4,22,142,1048,8704,80386,817786,9093340,109794556,1431360958,

%T 20047830262,300343272952,4793871035416,81232799446906,

%U 1456671526257106,27562347560513524,548844246683051860,11474015910364016086

%N Row sums of triangle A104990, which equals the matrix cube of triangle A104980.

%o (PARI) {a(n)=if(n<0,0,sum(k=0,n,(matrix(n+1,n+1,m,j,if(m==j,1,if(m==j+1,-m+1, -polcoeff((1-1/sum(i=0,m,i!*x^i))/x+O(x^m),m-j-1))))^-3)[n+1,k+1]))}

%Y Cf. A104990, A104980.

%K nonn

%O 0,2

%A _Paul D. Hanna_, Apr 10 2005

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Last modified September 24 01:21 EDT 2020. Contains 337315 sequences. (Running on oeis4.)