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.
%I A247939 #18 Sep 08 2022 08:46:09
%S A247939 6,13,48,176,2736,10928,174768,699056,11184816,727960800,2863311536,
%T A247939 183355069408,2967356682528,11728124029616,188313058624992,
%U A247939 12121838249371488,768906329487027264,3074457345618258608,196765296972010592800,3148244377723715041632
%N A247939 Sum of divisors of 2^prime(n)+1.
%C A247939 b-file computed with factorizations in Wagstaff link. a(166) corresponding to 2^983+1 is currently the first unknown term. - _Jens Kruse Andersen_, Sep 28 2014
%H A247939 Jens Kruse Andersen, <a href="/A247939/b247939.txt">Table of n, a(n) for n = 1..165</a>
%H A247939 Sam Wagstaff, <a href="http://homes.cerias.purdue.edu/~ssw/cun/">The Cunningham Project</a>
%F A247939 a(n) = A000203(A098640(n)). - _Michel Marcus_, Sep 27 2014
%p A247939 with(numtheory): A247939:=n->sigma(2^ithprime(n)+1): seq(A247939(n), n=1..20); # _Wesley Ivan Hurt_, Sep 27 2014
%t A247939 Table[DivisorSigma[1, 2^Prime[n] + 1], {n, 1, 20}]
%o A247939 (Magma) [SumOfDivisors(2^p+1): p in PrimesUpTo(100)];
%o A247939 (PARI) vector(50,n,sigma(2^prime(n)+1)) \\ _Derek Orr_, Sep 27 2014
%Y A247939 Cf. A000203, A069061, A098640.
%K A247939 nonn
%O A247939 1,1
%A A247939 _Vincenzo Librandi_, Sep 27 2014