OFFSET
1,2
COMMENTS
FORMULA
a(n) = denominator(Theta(5,n)) = denominator(Sum_{j=1..n} 1/(2*j-1)^5).
EXAMPLE
Rationals Theta(5,n): [1, 244/243, 762743/759375, 12820180976/12762815625, 3115356499043/3101364196875,...].
MATHEMATICA
r[n_] := Sum[1/(2*j-1)^5, {j, 1, n}]; (* or r[n_] := (PolyGamma[4, n+1/2] - PolyGamma[4, 1/2])/768 // FullSimplify; *) Table[r[n] // Denominator, {n, 1, 12}] (* Jean-François Alcover, Dec 02 2013 *)
CROSSREFS
KEYWORD
nonn,frac,easy
AUTHOR
Wolfdieter Lang, Oct 16 2009
STATUS
approved