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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.

A282945 Numbers k such that 5*2^k + 1 is a prime factor of a generalized Fermat number 7^(2^m) + 1 for some m.

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%I A282945 #17 Jan 16 2023 08:09:40
%S A282945 15,13165,23473,1777515
%N A282945 Numbers k such that 5*2^k + 1 is a prime factor of a generalized Fermat number 7^(2^m) + 1 for some m.
%H A282945 Anders Björn and Hans Riesel, <a href="http://dx.doi.org/10.1090/S0025-5718-98-00891-6">Factors of generalized Fermat numbers</a>, Math. Comp. 67 (1998), no. 221, pp. 441-446.
%H A282945 Anders Björn and Hans Riesel, <a href="http://dx.doi.org/10.1090/S0025-5718-05-01816-8">Table errata to "Factors of generalized Fermat numbers"</a>, Math. Comp. 74 (2005), no. 252, p. 2099.
%H A282945 Anders Björn and Hans Riesel, <a href="http://dx.doi.org/10.1090/S0025-5718-10-02371-9">Table errata 2 to "Factors of generalized Fermat numbers"</a>, Math. Comp. 80 (2011), pp. 1865-1866.
%H A282945 OEIS Wiki, <a href="/wiki/Generalized_Fermat_numbers">Generalized Fermat numbers</a>
%t A282945 lst = {}; Do[p = 5*2^n + 1; If[PrimeQ[p] && IntegerQ@Log[2, MultiplicativeOrder[7, p]], AppendTo[lst, n]], {n, 1, 13165, 2}]; lst
%Y A282945 Cf. A078304, A226366, A268661, A268662, A268663, A282946, A268664.
%Y A282945 Subsequence of A002254.
%K A282945 nonn,hard,more
%O A282945 1,1
%A A282945 _Arkadiusz Wesolowski_, Feb 25 2017