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A114117 Inverse of 1's counting matrix A114116. 2
1, 0, 1, -2, 1, 1, -1, -1, 1, 1, 0, -2, 0, 1, 1, 0, -1, -1, 0, 1, 1, 0, 0, -2, 0, 0, 1, 1, 0, 0, -1, -1, 0, 0, 1, 1, 0, 0, 0, -2, 0, 0, 0, 1, 1, 0, 0, 0, -1, -1, 0, 0, 0, 1, 1, 0, 0, 0, 0, -2, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, -1, -1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, -2, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, -1, -1, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 0, -2, 0, 0, 0, 0, 0, 0, 1 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,4

COMMENTS

Row sums are (1,1,0,0,0,.....) with g.f. 1+x. Diagonal sums have g.f. (1-x^2-x^3)/(1-x^3). Product of A114115 and the first difference matrix (1-x,x).

FORMULA

T(n, k)=sum{j=0..n, sum{i=0..n, C(floor((n+i)/2, j)C(j, floor((n+i)/2))}*(2*C(0, j-k)-C(1, j-k))}}.

EXAMPLE

Triangle begins

1;

0, 1;

-2, 1, 1;

-1,-1, 1, 1;

0,-2, 0, 1, 1;

0,-1,-1, 0, 1, 1;

0, 0,-2, 0, 0, 1, 1;

0, 0,-1,-1, 0, 0, 1, 1;

CROSSREFS

Sequence in context: A037910 A162781 A056975 * A144435 A173120 A025920

Adjacent sequences:  A114114 A114115 A114116 * A114118 A114119 A114120

KEYWORD

easy,sign,tabl

AUTHOR

Paul Barry (pbarry(AT)wit.ie), Nov 13 2005

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Last modified February 17 09:41 EST 2012. Contains 206009 sequences.