A130188 Denominators of rationals r(n) related to the z-sequence of the Sheffer matrix A060821 for Hermite polynomials.

1, 4, 4, 32, 16, 64, 64, 1024, 256, 1024, 1024, 8192, 4096, 16384, 16384, 524288, 65536, 262144, 262144, 2097152, 1048576, 4194304, 4194304, 67108864, 16777216, 67108864, 67108864, 536870912, 268435456, 1073741824

Offset

0,2

Comments

Numerators are A130187.

See A130187 for details on r(n):= A130187(n)/a(n) and the corresponding z-sequence for the Hermite matrix A060821.

Links

G. C. Greubel, Table of n, a(n) for n = 0..1000

Formula

a(n) = denominator(-2*z(2*n+1)), n>=0, with the e.g.f. for z(n) given in A130187.

Mathematica

F:= CoefficientList[Series[-2*(Exp[x^2/4] -1)/x, {x, 0, 75}], x]*Range[0, 75]!; Table[Denominator[-2*F[[2*n]]], {n, 1, 50}] (* G. C. Greubel, Jul 10 2018 *)

Crossrefs

Sequence in context: A120030 A138504 A002611 * A270676 A270625 A271019

Adjacent sequences: A130185 A130186 A130187 * A130189 A130190 A130191

Keyword

nonn,frac,easy

Author

Wolfdieter Lang Jun 01 2007

Status

approved