cp's OEIS Frontend

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.

A107056 Matrix inverse of A103247, so that T(n,k) = C(n,k)*A010842(n-k), read by rows.

Original entry on oeis.org

1, 3, 1, 10, 6, 1, 38, 30, 9, 1, 168, 152, 60, 12, 1, 872, 840, 380, 100, 15, 1, 5296, 5232, 2520, 760, 150, 18, 1, 37200, 37072, 18312, 5880, 1330, 210, 21, 1, 297856, 297600, 148288, 48832, 11760, 2128, 280, 24, 1, 2681216, 2680704, 1339200, 444864, 109872
Offset: 0

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Author

Paul D. Hanna, May 19 2005

Keywords

Comments

A103247(n,k) is the coefficient of x^k in the monic characteristic polynomial of the n X n matrix with 3's on the diagonal and 1's elsewhere.

Examples

			Triangle T begins:
1;
3,1;
10,6,1;
38,30,9,1;
168,152,60,12,1;
872,840,380,100,15,1;
5296,5232,2520,760,150,18,1; ...
where T(n,k) = A010842(n-k)*binomial(n,k).
Matrix logarithm L begins:
0;
-3,0;
-1,-6,0;
-2,-3,-9,0;
-6,-8,-6,-12,0;
-24,-30,-20,-10,-15,0; ...
where L(n,k) = L(n,0)*binomial(n,k),
with L(n,0)=-(n-1)! for n>1, L(1,0)=-3, L(0,0)=0.
		

Crossrefs

Programs

  • PARI
    T(n,k)=n!/k!*sum(j=0,n-k,2^(n-k-j)/(n-k-j)!)

Formula

T(n, k) = n!/k!*Sum_{j=0..n-k} 2^(n-k-j)/(n-k-j)!.