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%I #10 Dec 19 2019 05:48:41
%S 6,14,48,98,372,868,2784,7236,27744,64708,215040,541156,1947840,
%T 5168548,23046144,43129476,155189760,444228512,1398675600,3623742864,
%U 14636428992,33799504228,113272236000,299806597512,1154553386688,2755025768460,10476271399872,23113208752200
%N Sum of divisors of 2^n + 3^n.
%C The terms are never squares. For n>=2, 2^n+3^n falls into a pattern of quadratic non-residues, taken modulo 20: 13, 15, 17, 15, 13, 15, 17, 15, ... - _Jack Brennen_, Dec 25 2005
%C a(n) is always even because 2^n+3^n is never a quadratic residue modulo 15. - Jose Brox (tautocrona(AT)terra.es), Dec 27 2005
%H Amiram Eldar, <a href="/A114705/b114705.txt">Table of n, a(n) for n = 1..546</a>
%F a(n) = A000203(A007689(n)). - _Amiram Eldar_, Dec 19 2019
%e a(3)=48 because 2^3+3^3=8+27=35 has divisors 1,5,7,35 sum of which is 48.
%t Table[DivisorSigma[1, 2^n+3^n], {n, 1, 30}]
%Y Cf. A000203, A007689.
%K nonn
%O 1,1
%A _Zak Seidov_, Dec 26 2005
%E More terms from _Amiram Eldar_, Dec 19 2019
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