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 A126312 #3 Mar 31 2012 13:21:13 %S A126312 0,1,2,3,4,8,9,22,23,30,55,64,65,98,158,196,197,318,484,625,626,687, %T A126312 1042,1549,1973,2055,2056,2376,3471,5113,6558,6917,6918,8191,11763, %U A126312 17268,22277,23713,23714,24331,28360,40491,59362,76942,81754,82499 %N A126312 Fixed points of permutation A071661/A071662. %C A126312 Those i for which A071661(i)=i, i.e. for which A057163(A057164(i)) = A057164(A057163(i)). These appear to consist of just those general plane trees which are symmetric and will stay symmetric also after the underlying plane binary tree has been reflected, i.e. for which A057164(i)=i and A057164(A057163(i)) = A057163(i). See comments at A123050 and A080070. The sequence seems to give also the fixed points of the permutation A125977/A125978. %H A126312 D. Callan, <a href="http://www.stat.wisc.edu/~callan/papers/Motzkin_manifestation/">A Bijection on Dyck Paths and Its Cycle Structure</a>, 2006, 17pp. %K A126312 nonn %O A126312 0,3 %A A126312 _Antti Karttunen_, Jan 16 2007