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A091597 Triangle read by rows: T(n,0)=A001045(n), T(n,m)=T(n-1,m-1)+T(n-1,m). 2
1, 1, 1, 3, 2, 1, 5, 5, 3, 1, 11, 10, 8, 4, 1, 21, 21, 18, 12, 5, 1, 43, 42, 39, 30, 17, 6, 1, 85, 85, 81, 69, 47, 23, 7, 1, 171, 170, 166, 150, 116, 70, 30, 8, 1, 341, 341, 336, 316, 266, 186, 100, 38, 9, 1, 683, 682, 677, 652, 582, 452, 286, 138, 47, 10, 1, 1365, 1359, 1329 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,4

COMMENTS

A Jacobsthal-Pascal triangle.

Equals triangle M * Pascal's triangle, M = an infinite lower triangular Toeplitz matrix with A078008: [1, 0, 2, 2, 6, 10, 22, 42,...] in every column. [From Gary W. Adamson (qntmpkt(AT)yahoo.com), May 25 2009]

FORMULA

Number triangle T(n, k)=sum{j=0..n, binomial(n-j, k+j)2^j}; Riordan array (1/(1-x-2x^2), x/(1-x)); k-th column has g.f. (1/(1-x-2x^2))(x/(1-x))^k.

EXAMPLE

Rows start {1}, {1,1}, {3,2,1}, {5,5,3,1}, {11,10,8,4,1}...

CROSSREFS

Columns include A001045, A000975, A011377. Row sums are A059570.

A078008 [From Gary W. Adamson (qntmpkt(AT)yahoo.com), May 25 2009]

Sequence in context: A080883 A021315 A068389 * A091595 A132969 A132970

Adjacent sequences:  A091594 A091595 A091596 * A091598 A091599 A091600

KEYWORD

easy,nonn,tabl

AUTHOR

Paul Barry (pbarry(AT)wit.ie), Jan 23 2004

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Last modified February 14 07:16 EST 2012. Contains 205589 sequences.