A145614 - OEIS

A145614

Denominator of the polynomial A_l(x) = sum_{d=1..l-1} x^(l-d)/d for index l=2n+1 evaluated at x=3.

%I #4 Mar 31 2012 10:22:14

%S 2,4,20,280,280,3080,5720,2288,116688,3695120,25865840,594914320,

%T 2974571600,8923714800,86262576400,5348279736800,5348279736800,

%U 16044839210400,197886350261600,15222026943200,89157586381600

%N Denominator of the polynomial A_l(x) = sum_{d=1..l-1} x^(l-d)/d for index l=2n+1 evaluated at x=3.

%C For numerators see A145613. For general properties of A_l(x) see A145609.

%t m = 3; aa = {}; Do[k = 0; Do[k = k + m^(2 r + 1 - d)/d, {d, 1, 2 r}]; AppendTo[aa, Denominator[k]], {r, 1, 30}]; aa (*Artur Jasinski*)

%Y Cf. A145609 - A145640.

%K frac,nonn

%O 1,1

%A _Artur Jasinski_, Oct 14 2008

%E Edited by _R. J. Mathar_, Aug 21 2009