Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #13 Sep 01 2019 10:54:41
%S 3,1,4,7,8,12,39,30,48,140,168,200,576,522,1128,2688,2208,3572,12960,
%T 9350,17296,44520,54208,64680,158976,186048,361928,809200,826728,
%U 1169400,4131036,3010350,4876416,13862800,17256768,23639040,59720832,54018522,116538408,251395200,233917632,370248452,1319232096
%N Sum of positive divisors of A000032(n).
%H Amiram Eldar, <a href="/A272439/b272439.txt">Table of n, a(n) for n = 0..1000</a> (using Blair Kelly's data)
%H Blair Kelly, <a href="http://mersennus.net/fibonacci//">Fibonacci and Lucas Factorizations</a>
%F a(n) = A000203(A000032(n)).
%e a(2) = 4 because A000032(2) = 3 and A000203(3) = 4.
%t DivisorSigma[1, LucasL@ Range[0, 42]] (* _Michael De Vlieger_, Apr 29 2016 *)
%o (PARI) a(n) = sigma(fibonacci(n-1) + fibonacci(n+1));
%Y Cf. A000032, A000203.
%K nonn
%O 0,1
%A _Altug Alkan_, Apr 29 2016