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 A277909 #6 Nov 07 2016 09:12:20 %S A277909 2,4,6,14,20,23,33,35,37,43,46,50,60,64,66,76,90,93,103,105,116,127, %T A277909 140,144,147,154,163,167,200,206,215,247,275,285,287,293,295,303,313, %U A277909 323,337,340,344,363,365,410,427,430,433,435,440,476,483,495,497,523,527,533,536,555,566,596,623,625,665,667,676,694,696,714,747,757 %N A277909 Numbers n for which A277911(n) = n+1. %H A277909 Antti Karttunen, <a href="/A277909/b277909.txt">Table of n, a(n) for n = 1..481</a> %o A277909 (Scheme, with _Antti Karttunen_'s IntSeq-library) %o A277909 (define A277909 (MATCHING-POS 1 1 (lambda (n) (= (A277911 n) (+ 1 n))))) %Y A277909 Odd bisection of A277908. %Y A277909 One less than A277910. %Y A277909 Cf. A277911. %K A277909 nonn %O A277909 1,1 %A A277909 _Antti Karttunen_, Nov 05 2016