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 A243497 #13 Jul 29 2014 13:46:46
%S A243497 1,2,3,4,5,7,8,9,11,16,17,19,23,25,27,31,32,49,53,59,64,67,81,83,97,
%T A243497 103,121,125,127,128,131,169,227,241,243,256,277,289,311,331,343,361,
%U A243497 419,431,509,512,529,563,661,691,709,719,739,841,961,1009,1024,1433,1523,1619,1681,1787,1849,1879,2063
%N A243497 A243496 sorted into ascending order, with duplicates removed.
%C A243497 Matula-codes for trees which are almost "uniform", but which allow cases like 169, 841, 1009, 1681, 1849, ... where there is a special relation between prime index and the exponent. (Cf. the comments at A243496).
%C A243497 Differs from A214577 for the first time at n=31, where A214577(31)=227, while here we have 169 at that position, because it corresponds exactly to that "dual" case mentioned in A057546, in excess to those mentioned in A003238. Note that 169 = 13*13 = p_{2*3}^2.
%C A243497 a(0) = 1 stands for the empty tree.
%Y A243497 Cf. A214577 (a subsequence), A209638, A243494.
%K A243497 nonn
%O A243497 0,2
%A A243497 _Antti Karttunen_, Jun 07 2014