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A106513 A Pell-Pascal matrix. 2
1, 2, 1, 5, 3, 1, 12, 8, 4, 1, 29, 20, 12, 5, 1, 70, 49, 32, 17, 6, 1, 169, 119, 81, 49, 23, 7, 1, 408, 288, 200, 130, 72, 30, 8, 1, 985, 696, 488, 330, 202, 102, 38, 9, 1, 2378, 1681, 1184, 818, 532, 304, 140, 47, 10, 1, 5741, 4059, 2865, 2002, 1350, 836, 444, 187, 57 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

Row sums are A106514. Diagonal sums are A106515.

FORMULA

Riordan array (1/(1-2x-x^2), x/(1-x)); Number triangle T(n, 0)=A000129(n), T(n, k)=T(n-1, k-1)+T(n-1, k); T(n, k)=sum{j=0..floor((n+1)/2), binomial(n+1, 2j+k+1)2^j}.

EXAMPLE

Triangle begins

1;

2,1;

5,3,1;

12,8,4,1;

29,20,12,5,1;

70,49,32,17,6,1;

CROSSREFS

Sequence in context: A105728 A120095 A130197 * A054446 A164981 A047858

Adjacent sequences:  A106510 A106511 A106512 * A106514 A106515 A106516

KEYWORD

easy,nonn,tabl

AUTHOR

Paul Barry (pbarry(AT)wit.ie), May 05 2005

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Last modified February 17 16:32 EST 2012. Contains 206050 sequences.