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 A057548 #9 Aug 03 2017 00:39:15 %S A057548 1,3,7,8,17,18,20,21,22,45,46,48,49,50,54,55,57,58,59,61,62,63,64,129, %T A057548 130,132,133,134,138,139,141,142,143,145,146,147,148,157,158,160,161, %U A057548 162,166,167,169,170,171,173,174,175,176,180,181,183,184,185,187,188 %N A057548 A014486-indices of Catalan mountain ranges with no sea-level valleys, i.e., the rooted plane general trees with root degree = 1. %C A057548 This sequence is induced by the unary form of function 'list' (present in Lisp and Scheme) when it acts on symbolless S-expressions encoded by A014486/A063171. %H A057548 <a href="/index/Li#ListFunsOfLisp">Index entries for the sequences induced by list functions of Lisp</a> %F A057548 a(n) = A080300(A057547(n)) = A069770(A072795(n)). %Y A057548 We have A057515(A057548(n)) = 1 for all n. Row 0 of A072764. Column 1 of A085203. Cf. A057517, A057549, A057551. %K A057548 nonn %O A057548 0,2 %A A057548 _Antti Karttunen_, Sep 07 2000