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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.

A111838 Matrix log of triangle A111835, which shifts columns left and up under matrix 8th power; these terms are the result of multiplying each element in row n and column k by (n-k)!.

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%I A111838 #10 Jun 13 2017 22:36:29
%S A111838 0,1,0,-6,8,0,142,-48,64,0,31800,1136,-384,512,0,-159468264,254400,
%T A111838 9088,-3072,4096,0,-2481298801008,-1275746112,2035200,72704,-24576,
%U A111838 32768,0,1414130111428687344,-19850390408064,-10205968896,16281600,581632,-196608,262144,0
%N A111838 Matrix log of triangle A111835, which shifts columns left and up under matrix 8th power; these terms are the result of multiplying each element in row n and column k by (n-k)!.
%C A111838 Column k equals 8^k multiplied by column 0 (A111839) when ignoring zeros above the diagonal.
%F A111838 T(n, k) = 8^k*T(n-k, 0) = A111839(n-k) for n>=k>=0.
%e A111838 Matrix log of A111835, with factorial denominators, begins:
%e A111838 0;
%e A111838 1/1!, 0;
%e A111838 -6/2!, 8/1!, 0;
%e A111838 142/3!, -48/2!, 64/1!, 0;
%e A111838 31800/4!, 1136/3!, -384/2!, 512/1!, 0;
%e A111838 -159468264/5!, 254400/4!, 9088/3!, -3072/2!, 4096/1!, 0; ...
%o A111838 (PARI) T(n,k,q=8)=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 || j==1,B[i,j]=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 A111838 Cf. A111835, A111839 (column 0); log matrices: A110504 (q=-1), A111813 (q=2), A111815 (q=3), A111818 (q=4), A111823 (q=5), A111828 (q=6), A111833 (q=7).
%K A111838 frac,sign,tabl
%O A111838 0,4
%A A111838 _Gottfried Helms_ and _Paul D. Hanna_, Aug 22 2005