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A107671 Triangular matrix T, read by rows, that satisfies: T = D + SHIFT_LEFT(T^3) where SHIFT_LEFT shifts each row 1 place left and D is the diagonal matrix {1,2,3,...}. 6
1, 8, 2, 513, 27, 3, 81856, 2368, 64, 4, 23846125, 469625, 7625, 125, 5, 10943504136, 160767720, 1898856, 19656, 216, 6, 7250862593527, 83548607478, 776598305, 6081733, 43561, 343, 7, 6545029128786432, 61068815111168, 465690017280 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,2

FORMULA

Matrix diagonalization method: define triangular matrix P by P(n, k) = ((n+1)^3)^(n-k)/(n-k)!, n>=k>=0 and diagonal matrix D(n, n) = n+1, then T is given by T = P^-1*D*P.

EXAMPLE

Triangle T begins:

1;

8,2;

513,27,3;

81856,2368,64,4;

23846125,469625,7625,125,5;

10943504136,160767720,1898856,19656,216,6;

7250862593527,83548607478,776598305,6081733,43561,343,7; ...

The matrix cube T^3 shifts each row right 1 place,

dropping the diagonal D and putting A006690 in column 0:

1;

56,8;

7965,513,27;

2128064,81856,2368,64;

914929500,23846125,469625,7625,125;

576689214816,10943504136,160767720,1898856,19656,216; ...

PROG

(PARI) {T(n, k)=local(P=matrix(n+1, n+1, r, c, if(r>=c, (r^3)^(r-c)/(r-c)!)), D=matrix(n+1, n+1, r, c, if(r==c, r))); if(n>=k, (P^-1*D*P)[n+1, k+1])}

CROSSREFS

Cf. A107667, A107672 (column 0), A107673, A107674 (matrix square), A107676 (matrix cube), A006690.

Sequence in context: A188898 A176860 A093082 * A154538 A154166 A010521

Adjacent sequences:  A107668 A107669 A107670 * A107672 A107673 A107674

KEYWORD

nonn,tabl

AUTHOR

Paul D. Hanna (pauldhanna(AT)juno.com), Jun 07 2005

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Last modified February 14 23:53 EST 2012. Contains 205689 sequences.