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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.

A110504 Triangle, read by rows, which equals the matrix logarithm of the triangle A110503.

Original entry on oeis.org

0, 1, 0, 3, -1, 0, 7, -3, 1, 0, 30, -7, 3, -1, 0, 144, -30, 7, -3, 1, 0, 876, -144, 30, -7, 3, -1, 0, 6084, -876, 144, -30, 7, -3, 1, 0, 48816, -6084, 876, -144, 30, -7, 3, -1, 0, 438624, -48816, 6084, -876, 144, -30, 7, -3, 1, 0, 4389120, -438624, 48816, -6084, 876, -144, 30, -7, 3, -1, 0
Offset: 0

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Author

Paul D. Hanna, Jul 23 2005

Keywords

Comments

The unsigned columns this triangle are all equal to A110505. Triangle A110503 shifts one column left under matrix inverse.

Examples

			Triangle begins:
0;
1/1!, 0;
3/2!, -1/1!, 0;
7/3!, -3/2!, 1/1!, 0;
30/4!, -7/3!, 3/2!, -1/1!, 0;
144/5!, -30/4!, 7/3!, -3/2!, 1/1!, 0;
876/6!, -144/5!, 30/4!, -7/3!, 3/2!, -1/1!, 0;
6084/7!, -876/6!, 144/5!, -30/4!, 7/3!, -3/2!, 1/1!, 0; ...
Unsigned columns all equal A110505.
Exponential function of matrix equals A110503:
1;
1,1;
1,-1,1;
1,-2,1,1;
1,-1,1,-1,1;
1,-1,1,-2,1,1;
1,-1,1,-1,1,-1,1;
1,-1,1,-1,1,-2,1,1; ...
		

Crossrefs

Cf. A110503 (matrix exponential), A110505 (unsigned columns).

Programs

  • PARI
    T(n,k)=local(M=matrix(n+1,n+1,r,c,if(r>=c, if(r==c || c%2==1,1,if(r%2==0 && r==c+2,-2,-1))))); sum(i=1,#M,-(M^0-M)^i/i)[n+1,k+1]

Formula

T(n, k) = (-1)^k*A110505(n-k).