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A298611 Expansion of (1 - 6*x + x^2 - 8*x^3 + 16*x^4)^(-1/2). 2
1, 3, 13, 67, 349, 1875, 10285, 57123, 320317, 1809587, 10283149, 58714627, 336579101, 1935878419, 11166265837, 64566715363, 374148669949, 2172215118963, 12632572359757, 73575490895043, 429102329027293, 2505638311638739, 14647279574704045, 85710562407867555 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

See A299499 for a family of related polynomials.

LINKS

Table of n, a(n) for n=0..23.

FORMULA

a(n) = Sum_{k=0..n} 2^(n-k)*binomial(n,k)*hypergeom([-k, k-n, k-n], [1, -n], 2).

D-finite with recurrence: (16*n-32)*a(n-4) + (-8*n+12)*a(n-3) + (n-1)*a(n-2) + (-6*n+3)*a(n-1) + n*a(n) = 0.

MAPLE

a := n -> add(2^(n-k)*binomial(n, k)*hypergeom([-k, k-n, k-n], [1, -n], 2), k=0..n): seq(simplify(a(n)), n=0..23);

MATHEMATICA

CoefficientList[Series[(1 - 6 x + x^2 - 8 x^3 + 16 x^4)^(-1/2), {x, 0, 23}], x]

CROSSREFS

Cf. A299499, A299502.

Sequence in context: A302303 A201713 A333083 * A136784 A284717 A027277

Adjacent sequences:  A298608 A298609 A298610 * A298612 A298613 A298614

KEYWORD

nonn

AUTHOR

Peter Luschny, Feb 15 2018

STATUS

approved

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Last modified April 6 12:19 EDT 2020. Contains 333273 sequences. (Running on oeis4.)