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 A256354 #11 Apr 09 2024 16:00:39 %S A256354 115,2563,3523,5071,9193,10873,12223,12811,13231,15775,19111,20203, %T A256354 23089,25831,27007,28171,34189,39859,40033,43361,55033,57871,58813, %U A256354 74371,84253,89377,93043,95833,101683,117001,125359,126673,128953,131029,134527,137467,138193 %N A256354 Composites in base 10 that remain composite in exactly four bases b, 2 <= b <= 10, expansions interpreted as decimal numbers. %H A256354 Sebastian Petzelberger, <a href="/A256354/b256354.txt">Table of n, a(n) for n = 1..10000</a> %H A256354 Carlos Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_024.htm">PP&P Puzzle 24: Primes in several bases</a> %Y A256354 Cf. A052026, A256350-A256356, A038537, A052027-A052033, A084482, A236356. %K A256354 nonn,base %O A256354 1,1 %A A256354 _Sebastian Petzelberger_, Mar 25 2015