cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A225905 Denominator of Sum_{k=1..n} 1/L(k) where L(n) is the n-th Lucas number (A000204).

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%I A225905 #8 Mar 11 2015 11:23:09
%S A225905 1,3,12,84,924,2772,80388,3778236,35893242,1471622922,292852961478,
%T A225905 3367809056997,1754628518695437,493050613753417797,
%U A225905 61138276105423806828,134932175364670341669396,481842798227237790101413116,154671538230943330622553610236
%N A225905 Denominator of Sum_{k=1..n} 1/L(k) where L(n) is the n-th Lucas number (A000204).
%e A225905 1, 4/3, 19/12, 145/84, 1679/924, 5191/2772, ... = A225904/A225905.
%t A225905 Denominator[Table[Sum[1/LucasL[k], {k, 1, n}], {n, 1, 30}]]
%t A225905 Denominator[Accumulate[1/LucasL[Range[20]]]] (* _Harvey P. Dale_, Mar 11 2015 *)
%Y A225905 Cf. A000204, A059248, A035105, A225904.
%K A225905 nonn,frac,easy
%O A225905 1,2
%A A225905 _Michel Lagneau_, May 20 2013