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A107269 Diagonal sums of A107267, viewed as a number triangle. 1
1, 0, 1, 1, 3, 6, 16, 44, 136, 457, 1669, 6547, 27334, 120465, 557094, 2692528, 13564940, 71102869, 387132791, 2185813423, 12775466408, 77154694819, 480630407368, 3083443893896, 20344187534051, 137884769704754 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,5

LINKS

Table of n, a(n) for n=0..25.

FORMULA

a(n)=sum{k=0..n, sum{j=0..n-2k, (1/(j+1))C(j+1, n-2k-j+1)C(n-2k, j)k^j}}

CROSSREFS

Sequence in context: A274295 A192676 A202846 * A086811 A106361 A113040

Adjacent sequences:  A107266 A107267 A107268 * A107270 A107271 A107272

KEYWORD

easy,nonn

AUTHOR

Paul Barry, May 15 2005

STATUS

approved

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Last modified December 5 11:32 EST 2016. Contains 278763 sequences.