A101106 A Chebyshev transform of the central Delannoy numbers.

1, 3, 12, 57, 283, 1440, 7461, 39159, 207492, 1107549, 5946543, 32080032, 173748913, 944185827, 5145534876, 28110823401, 153904324315, 844210620000, 4638535417701, 25524848838951, 140647394816532, 775943203532733

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