A107724 - OEIS

A107724

Matrix logarithm of triangle A107719, read by rows.

0, 1, 0, 4, 2, 0, 31, 10, 3, 0, 343, 88, 19, 4, 0, 4855, 1066, 199, 31, 5, 0, 83209, 16216, 2779, 382, 46, 6, 0, 1670743, 295360, 47791, 6130, 655, 64, 7, 0, 38436673, 6254824, 970849, 119182, 11929, 1036, 85, 8, 0, 996825703, 150917560, 22697647, 2703730

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OFFSET

0,4

COMMENTS

Also equals one-third of the matrix logarithm of A107717. Column 0 is A107725.

LINKS

Table of n, a(n) for n=0..48.

EXAMPLE

Triangle begins:

1,0;

4,2,0;

31,10,3,0;

343,88,19,4,0;

4855,1066,199,31,5,0;

83209,16216,2779,382,46,6,0;

1670743,295360,47791,6130,655,64,7,0;

38436673,6254824,970849,119182,11929,1036,85,8,0; ...

PROG

(PARI) T(n, k)=local(L, M=matrix(n+1, n+1, m, j, if(m>=j, if(m==j, 1, if(m==j+1, -3*j, polcoeff(1/sum(i=0, m-j, prod(r=0, i-1, 3*r+1)*x^i)+O(x^m), m-j)))))^-1); L=sum(i=1, #M, (-1)^(i-1)*(M-M^0)^i/i); return(if(n<k || k<0, 0, L[n+1, k+1]/3))

CROSSREFS

Cf. A107717, A107719.

Sequence in context: A022696 A371076 A019155 * A247092 A177715 A164789

Adjacent sequences: A107721 A107722 A107723 * A107725 A107726 A107727

KEYWORD

nonn,tabl

AUTHOR

Paul D. Hanna, May 30 2005

STATUS

approved