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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A111810 Matrix log of triangle A098539, which shifts columns left and up under matrix square; these terms are the result of multiplying each element in row n and column k by (n-k)!.

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%I A111810 #7 Jun 13 2017 22:33:21
%S A111810 0,1,0,2,2,0,10,4,4,0,88,20,8,8,0,1096,176,40,16,16,0,11856,2192,352,
%T A111810 80,32,32,0,-402480,23712,4384,704,160,64,64,0,-1891968,-804960,47424,
%U A111810 8768,1408,320,128,128,0,36024603264,-3783936,-1609920,94848,17536,2816,640,256,256,0
%N A111810 Matrix log of triangle A098539, which shifts columns left and up under matrix square; these terms are the result of multiplying each element in row n and column k by (n-k)!.
%C A111810 Column k equals 2^k times column 0 (A111811) when ignoring zeros above the diagonal.
%F A111810 T(n, k) = 2^k*T(n-k, 0) = 2^k*A111811(n-k) for n>=k>=0.
%e A111810 Matrix log of A098539, with factorial denominators, begins:
%e A111810 0;
%e A111810 1/1!, 0;
%e A111810 2/2!, 2/1!, 0;
%e A111810 10/3!, 4/2!, 4/1!, 0;
%e A111810 88/4!, 20/3!, 8/2!, 8/1!, 0;
%e A111810 1096/5!, 176/4!, 40/3!, 16/2!, 16/1!, 0;
%e A111810 11856/6!, 2192/5!, 352/4!, 80/3!, 32/2!, 32/1!, 0; ...
%o A111810 (PARI) T(n,k,q=2)=local(A=Mat(1),B);if(n<k || k<0,0, for(m=1,n+1,B=matrix(m,m);for(i=1,m, for(j=1,i, if(j==i,B[i,j]=1,if(j==1,B[i,j]=(A^q)[i-1,1], B[i,j]=(A^q)[i-1,j-1]));));A=B); B=sum(i=1,#A,-(A^0-A)^i/i);return((n-k)!*B[n+1,k+1]))
%Y A111810 Cf. A098539 (triangle), A111811 (column 0), A111813 (variant), A111941 (q=-1), A111843 (q=3), A111848 (q=4).
%K A111810 frac,sign,tabl
%O A111810 0,4
%A A111810 _Paul D. Hanna_, Aug 22 2005