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A113140 Diagonal sums of a Delannoy related triangle. 1
1, 3, 14, 68, 347, 1819, 9712, 52532, 286905, 1578679, 8738278, 48601968, 271406347, 1520725095, 8545396208, 48138689272, 271768537793, 1537212749339, 8709732836238, 49423440297324, 280835252080651, 1597731101233763 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

Diagonal sums of A113139.

FORMULA

a(n)=sum{k=0..floor(n/2), sum{j=0..n-k, C(n-2k, j)C(n-k+j, k+j)}}.

CROSSREFS

Sequence in context: A002320 A151323 A181662 * A151324 A121185 A199314

Adjacent sequences:  A113137 A113138 A113139 * A113141 A113142 A113143

KEYWORD

easy,nonn

AUTHOR

Paul Barry (pbarry(AT)wit.ie), Oct 15 2005

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Last modified February 15 21:56 EST 2012. Contains 205860 sequences.