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 A126031 #15 Dec 21 2024 17:59:03 %S A126031 2,5,13,37,109,317,947,2837,8501,25471,76403,229199,687593,2062759, %T A126031 6188263,18564769,55694299,167082893,501248653,1503745949,4511237741, %U A126031 13533713213,40601139629,121803418861,365410256543,1096230769619,3288692308841,9866076926507,29598230779511 %N A126031 a(n) is the largest prime < 3*a(n-1) for n > 1, with a(1) = 2. %H A126031 Artur Jasinski, <a href="/A126031/b126031.txt">Table of n, a(n) for n = 1..40</a> %t A126031 NestList[NextPrime[3#,-1]&,2,30] (* _Harvey P. Dale_, Feb 03 2012 *) %Y A126031 Similar sequences for a(n) = largest prime < m*a(n-1): A006992 (m=2), this sequence (3), A124190 (4), A126033 (5), A126034 (6), A126035 (7), A126036 (8), A126037 (9), A124262 (10), A126039 (11), A126040 (12), A124339 (100), A124361 (1000), A124364 (10000), A124362 (100000), A124368 (1000000). %K A126031 nonn %O A126031 1,1 %A A126031 _Artur Jasinski_, Dec 16 2006