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 A242880 #29 Jan 10 2025 15:51:55 %S A242880 1729,4033,8321,12801,65281,130561,348161,3225601,8355841,8384513, %T A242880 16773121,40280065,104988673,2147418113,4294901761,4294967297, %U A242880 53282340865,68719214593,137439477761,1099510579201,1911029760001,2199021158401,8796097216513,281474959933441,9007199388958721,576460753377165313,2305843011361177601,18446744073709551617 %N A242880 Numbers that are both Poulet and Proth. %C A242880 Intersection of A080075 and A001567. %C A242880 a(1) = 1729 is known as the Hardy-Ramanujan number (see A001235). - _Omar E. Pol_, Jun 14 2014 %H A242880 Giovanni Resta, <a href="http://www.numbersaplenty.com/both_Poulet_and_Proth.html">Poulet n and Proth n</a>. %Y A242880 Cf. A080075 (Proth numbers), A001567 (Poulet numbers). %K A242880 nonn %O A242880 1,1 %A A242880 _Lear Young_, May 25 2014 %E A242880 a(20)-a(28) from _Max Alekseyev_, May 28 2014