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 A257512 #17 May 04 2015 02:16:18 %S A257512 10,18,25,34,41,54,56,66,73,86,88,102,110,117,119,130,137,150,152,166, %T A257512 174,181,183,198,206,213,222,229,243,244,246,258,265,278,280,294,302, %U A257512 309,311,326,334,341,350,357,371,372,374,390,398,405,414,421,435,436,446,453,467,468,483,491,498,499,501,514 %N A257512 Those vertices of the binary beanstalk whose children are both leaves. %C A257512 Numbers n for which both A079559(A213723(n)) and A079559(A213724(n)) are zero. %C A257512 Numbers which occur twice in A257507. %H A257512 Antti Karttunen, <a href="/A257512/b257512.txt">Table of n, a(n) for n = 1..16384</a> %H A257512 Paul Tek, <a href="/A179016/a179016.png">Illustration of how natural numbers in range 0 .. 133 are organized as a binary tree in the binary beanstalk</a> %e A257512 10 is present, because A011371(12) = A011371(13) = 10, and both 12 and 13 are terms of A055938. See also Paul Tek's illustration. %o A257512 (Scheme, with _Antti Karttunen_'s IntSeq-library) %o A257512 (define A257512 (MATCHING-POS 1 0 (lambda (n) (and (zero? (A079559 (A213723 n))) (zero? (A079559 (A213724 n))))))) %Y A257512 Cf. A011371, A055938, A079559, A213723, A213724, A257507, A257265. %Y A257512 First differences: A256490. %Y A257512 Subsequence of A005187, A213717 and A257508. %K A257512 nonn %O A257512 1,1 %A A257512 _Antti Karttunen_, May 03 2015