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A106268 Number triangle T(n,k)=binomial(k-n,n-k)(-1)^(n-k)= if(k<=n, (0^(n-k)+binomial(2(n-k),n-k))/2,0); Riordan array (1/(2-C(x)),x) where C(x) is g.f. for Catalan numbers A000108. 2
1, 1, 1, 3, 1, 1, 10, 3, 1, 1, 35, 10, 3, 1, 1, 126, 35, 10, 3, 1, 1, 462, 126, 35, 10, 3, 1, 1, 1716, 462, 126, 35, 10, 3, 1, 1, 6435, 1716, 462, 126, 35, 10, 3, 1, 1, 24310, 6435, 1716, 462, 126, 35, 10, 3, 1, 1, 92378, 24310, 6435, 1716, 462, 126, 35, 10, 3, 1, 1, 352716 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,4

COMMENTS

Triangle includes A088218.

Rows sums are A024718. Diagonal sums are A106269. Inverse is A106270.

EXAMPLE

Triangle begins

1;

1,1;

3,1,1;

10,3,1,1;

35,10,3,1,1;

CROSSREFS

Sequence in context: A176482 A045912 A158695 * A060543 A185996 A176157

Adjacent sequences:  A106265 A106266 A106267 * A106269 A106270 A106271

KEYWORD

easy,nonn,tabl

AUTHOR

Paul Barry (pbarry(AT)wit.ie), Apr 28 2005

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Last modified February 12 14:01 EST 2012. Contains 205413 sequences.