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 A262053 #28 Jun 30 2019 10:42:35
%S A262053 185,217,301,481,1111,1261,1333,1729,2465,2701,3421,3565,3589,3913,
%T A262053 5713,6533,8365,10585,11041,11137,12209,14701,15841,17329,18361,20017,
%U A262053 21049,22049,29341,31021,31621,34441,36301,38081,39305,39493,41041,43621,44801,46657
%N A262053 Euler pseudoprimes to base 6: composite integers such that abs(6^((n - 1)/2)) == 1 mod n.
%H A262053 Amiram Eldar, <a href="/A262053/b262053.txt">Table of n, a(n) for n = 1..10000</a> (terms 1..86 from Daniel Lignon)
%t A262053 eulerPseudoQ[n_?PrimeQ, b_] = False; eulerPseudoQ[n_, b_] := Block[{p = PowerMod[b, (n - 1)/2, n]}, p == Mod[1, n] || p == Mod[-1, n]]; Select[2 Range[25000] + 1, eulerPseudoQ[#, 6] &] (* _Michael De Vlieger_, Sep 09 2015, after _Jean-François Alcover_ at A006970 *)
%o A262053 (PARI) for(n=1, 1e5, if( Mod(6, (2*n+1))^n == 1 || Mod(6, (2*n+1))^n == 2*n && bigomega(2*n+1) != 1 , print1(2*n+1", "))); \\ _Altug Alkan_, Oct 11 2015
%Y A262053 Cf. A006970 (base 2), A262051 (base 3), A262052 (base 5), this sequence (base 6), A262054 (base 7), A262055 (base 8).
%K A262053 nonn
%O A262053 1,1
%A A262053 _Daniel Lignon_, Sep 09 2015