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 A252801 #23 Jun 30 2021 19:28:58
%S A252801 2,5,7,13,17,23,29,31,37,41,43
%N A252801 Primes whose trajectories under the map x -> A039951(x) enter the cycle {2, 1093}.
%e A252801 The trajectory of 31 under the given map starts 31, 7, 5, 2, 1093, 2, 1093, ..., entering the given cycle, so 31 is a term of the sequence.
%Y A252801 Cf. A039951, A244550, A252802, A252812.
%K A252801 nonn,hard,more
%O A252801 1,1
%A A252801 _Felix Fröhlich_, Dec 22 2014
%E A252801 Name edited by _Felix Fröhlich_, Jun 19 2021