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A154930 Inverse of Fibonacci convolution array A154929. 1
1, -2, 1, 5, -4, 1, -15, 14, -6, 1, 51, -50, 27, -8, 1, -188, 187, -113, 44, -10, 1, 731, -730, 468, -212, 65, -12, 1, -2950, 2949, -1956, 970, -355, 90, -14, 1, 12235, -12234, 8291, -4356, 1785, -550, 119, -16, 1, -51822, 51821, -35643, 19474, -8612, 3021 (list; table; graph; refs; listen; history; internal format)
OFFSET

0,2

COMMENTS

Alternating sign version of A104259. Row sums are (-1)^n*A033321. First column is (-1)^n*A007317.

FORMULA

Riordan array ((1/(1+x))c(-x/(1+x)), (x/(1+x))c(x/(1+x))), c(x) the g.f. of A000108;

Riordan array ((sqrt(1+6x+5x^2)-x-1)/(2x(1+x)),(sqrt(1+6x+5x^2)-x-1)/(2(1+x)));

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

EXAMPLE

Triangle begins

1,

-2, 1,

5, -4, 1,

-15, 14, -6, 1,

51, -50, 27, -8, 1,

-188, 187, -113, 44, -10, 1,

731, -730, 468, -212, 65, -12, 1,

-2950, 2949, -1956, 970, -355, 90, -14, 1

Production array is

-2, 1,

1, -2, 1,

-1, 1, -2, 1,

1, -1, 1, -2, 1,

-1, 1, -1, 1, -2, 1,

1, -1, 1, -1, 1, -2, 1,

-1, 1, -1, 1, -1, 1, -2, 1

or ((1-x-x^2)/(1+x),x) beheaded.

CROSSREFS

Sequence in context: A128738 A193673 A126181 * A104259 A137650 A171515

Adjacent sequences:  A154927 A154928 A154929 * A154931 A154932 A154933

KEYWORD

easy,sign,tabl

AUTHOR

Paul Barry (pbarry(AT)wit.ie), Jan 17 2009

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Last modified February 14 11:36 EST 2012. Contains 205623 sequences.