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A188463 Coefficient array of the second column of the inverse of the Riordan array ((1+(r+1)x)/(1+(r+2)x+rx^2), x/(1+(r+2)x+rx^2)). 1
1, 3, 1, 7, 7, 1, 15, 30, 12, 1, 31, 103, 79, 18, 1, 63, 312, 387, 166, 25, 1, 127, 873, 1586, 1085, 305, 33, 1, 255, 2314, 5768, 5719, 2545, 512, 42, 1, 511, 5899, 19261, 25994, 16661, 5285, 805, 52, 1, 1023, 14604, 60337, 106009, 92008, 41881, 10038, 1204, 63, 1 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

First column is A000225. Row sums are A128714(n+2). Diagonal sums are A188464.

LINKS

Table of n, a(n) for n=0..54.

FORMULA

G.f.: ((x-1)*sqrt(x^2*(y^2+4)-2*x*(y+2)+1)+x^2*(2-y)-x*(y+3)+1)/(2*x^3*y*(1+y-x)).

MAPLE

Triangle begins

1,

3, 1,

7, 7, 1,

15, 30, 12, 1,

31, 103, 79, 18, 1,

63, 312, 387, 166, 25, 1,

127, 873, 1586, 1085, 305, 33, 1,

255, 2314, 5768, 5719, 2545, 512, 42, 1,

511, 5899, 19261, 25994, 16661, 5285, 805, 52, 1

CROSSREFS

Cf. A119308.

Sequence in context: A322753 A136035 A132307 * A319298 A101748 A058606

Adjacent sequences:  A188460 A188461 A188462 * A188464 A188465 A188466

KEYWORD

nonn,tabl,easy

AUTHOR

Paul Barry, Apr 01 2011

STATUS

approved

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Last modified December 7 17:41 EST 2019. Contains 329847 sequences. (Running on oeis4.)