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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.

A106338 Triangle T, read by rows, equal to the matrix inverse of the triangle defined by [T^-1](n,k) = A075263(n,k)/n!, for n>=k>=0.

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%I A106338 #10 Sep 11 2017 05:49:12
%S A106338 1,1,-1,1,-3,2,1,-9,14,-6,1,-45,110,-90,24,1,-585,1670,-1710,744,-120,
%T A106338 1,-21105,61670,-66150,32424,-7560,720,1,-1858185,5439350,-5864670,
%U A106338 2925384,-728280,91440,-5040,1,-367958745,1077215510,-1161894510,580489224,-145567800,18961200,-1285200,40320,1
%N A106338 Triangle T, read by rows, equal to the matrix inverse of the triangle defined by [T^-1](n,k) = A075263(n,k)/n!, for n>=k>=0.
%C A106338 Row sums are zero after the initial row. Absolute row sums equal A106339.
%F A106338 Also, T(n, k) = k!*A106340(n, k), where A106340 is the matrix inverse of the triangle formed from (n-k)!*A008278(n, k), n>=k>=0 and A008278 is the triangle of Stirling numbers of 2nd kind.
%e A106338 Triangle begins:
%e A106338 1;
%e A106338 1,-1;
%e A106338 1,-3,2;
%e A106338 1,-9,14,-6;
%e A106338 1,-45,110,-90,24;
%e A106338 1,-585,1670,-1710,744,-120;
%e A106338 1,-21105,61670,-66150,32424,-7560,720;
%e A106338 1,-1858185,5439350,-5864670,2925384,-728280,91440,-5040; ...
%e A106338 The matrix inverse T^-1 begins:
%e A106338 1;
%e A106338 1,1;
%e A106338 1,3/2,1/2;
%e A106338 1,2,7/6,1/6;
%e A106338 1,5/2,25/12,5/8,1/24;
%e A106338 1,3,13/4,3/2,31/120,1/120;
%e A106338 1,7/2,14/3,35/12,301/360,7/80,1/720; ...
%e A106338 where [T^-1](n,k) = A075263(n,k)/n!.
%e A106338 Each row n of the matrix inverse equals the initial
%e A106338 (n+1) fractional coefficients of (x/log(1+x))^n,
%e A106338 which are listed below for n=1,2,3,...,9:
%e A106338 1; 1/2,-1/12,1/24,-19/720,3/160,-863/60480,275/24192,...
%e A106338 1,1; 1/12,0,-1/240,1/240,-221/60480,19/6048,...
%e A106338 1,3/2,1/2; 0,1/240,-1/480,1/945,-11/20160,47/172800,...
%e A106338 1,2,7/6,1/6; -1/720,0,1/3024,-1/3024,199/725760,...
%e A106338 1,5/2,25/12,5/8,1/24; 0,-1/6048,1/12096,-19/725760,...
%e A106338 1,3,13/4,3/2,31/120,1/120; 1/30240,0,-1/57600,1/57600,...
%e A106338 1,7/2,14/3,35/12,301/360,7/80,1/720; 0,1/172800,...
%e A106338 1,4,19/3,5,81/40,23/60,127/5040,1/5040; -1/1209600,0,...
%e A106338 1,9/2,33/4,63/8,331/80,37/32,605/4032,17/2688,1/40320; 0,...
%t A106338 rows = 10; Tinv = Table[(1/n!)*PadRight[CoefficientList[x^(n+1)*Sum[k^n * (1-x)^k, {k, 0, Infinity}], x], rows], {n, 0, rows-1}]; T = Inverse[Tinv ]; Table[T[[n, k]], {n, 1, rows}, {k, 1, n}] // Flatten (* _Jean-François Alcover_, Sep 11 2017 *)
%o A106338 (PARI) T(n,k)=(M=matrix(n+1,n+1,m,j,if(m>=j, polcoeff((-x/log(1-x+x^2*O(x^n)))^m,j-1)))^-1)[n+1,k+1]
%o A106338 (PARI) T(n,k)=(-1)^n*k!*(matrix(n+1,n+1,r,c,if(r>=c,(r-c)!* sum(m=0,r-c+1,(-1)^(r-c+1-m)*m^r/m!/(r-c+1-m)!)))^-1)[n+1,k+1]
%Y A106338 Cf. A075263, A106340, A106339, A008278, A002206.
%K A106338 sign,tabl
%O A106338 0,5
%A A106338 _Paul D. Hanna_, May 01 2005