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.

A193294 Sum of even divisors of Fibonacci(n).

This page as a plain text file.
%I A193294 #13 May 13 2013 01:54:20
%S A193294 0,0,2,0,0,14,0,0,36,0,0,390,0,0,744,0,0,5040,0,0,11816,0,0,154752,0,
%T A193294 0,213840,0,0,1999872,0,0,3564360,0,0,46656000,0,0,63517896,0,0,
%U A193294 526048320,0,0,1465647264,0,0,16665772032,0,0,20377766312,0,0,173039328000
%N A193294 Sum of even divisors of Fibonacci(n).
%H A193294 Charles R Greathouse IV, <a href="/A193294/b193294.txt">Table of n, a(n) for n = 1..1000</a>
%e A193294 a(6) = 14 because Fibonacci(6) = 8, and the sum of the even divisors {2, 4, 8} = 14.
%t A193294 Table[Total[Select[Divisors[Fibonacci[n]], EvenQ[ # ]&]], {n, 75}]
%o A193294 (PARI) a(n)=if(n%3,0,2*sigma(fibonacci(n)/2)) \\ _Charles R Greathouse IV_, Jul 31 2011
%Y A193294 Cf. A000045, A193291.
%K A193294 nonn
%O A193294 1,3
%A A193294 _Michel Lagneau_, Jul 21 2011