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A101106 A Chebyshev transform of the central Delannoy numbers. 0
1, 3, 12, 57, 283, 1440, 7461, 39159, 207492, 1107549, 5946543, 32080032, 173748913, 944185827, 5145534876, 28110823401, 153904324315, 844210620000, 4638535417701, 25524848838951, 140647394816532, 775943203532733 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

Image of 1/sqrt(1-6x+x^2) under the mapping that takes g(x) to (1/(1+x^2))g(x/(1+x^2)).

LINKS

Table of n, a(n) for n=0..21.

FORMULA

G.f.: 1/sqrt(1-6x+3x^2-6x^3+x^4); a(n)=sum{k=0..n, binomial(n-k, k)(-1)^k*A001850(n-2k)}.

D-finite with recurrence: n*a(n) +3*(-2*n+1)*a(n-1) +3*(n-1)*a(n-2) +3*(-2*n+3)*a(n-3) +(n-2)*a(n-4)=0. - R. J. Mathar, Feb 20 2015

CROSSREFS

Sequence in context: A027140 A110309 A263667 * A165310 A133158 A328295

Adjacent sequences:  A101103 A101104 A101105 * A101107 A101108 A101109

KEYWORD

nonn

AUTHOR

Paul Barry, Dec 01 2004

STATUS

approved

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Last modified November 23 17:10 EST 2020. Contains 338595 sequences. (Running on oeis4.)