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 A160356 #8 Dec 04 2015 13:39:34 %S A160356 1,2,3,-4,5,6,7,-8,9,-10,11,-12,13,-14,15,-16,17,18,19,-20,21,-22,-23, %T A160356 24,-25,26,-27,28,-29,30,-31,32,33,34,-35,36,-37,-38,39,-40,41,-42,43, %U A160356 -44,45,-46,47,-48,49,-50,51,-52,53,-54,55,-56,57,-58,59,-60,61,-62,63 %N A160356 First differences of Recamán's sequence A005132. %F A160356 a(n) = A005132(n)-A005132(n-1) = n*A160357(n). %F A160356 As a set, A160356 = A057165 union -A057166. %Y A160356 Cf. A005132, A057165, A057166, A065056, A160357. %K A160356 sign %O A160356 1,2 %A A160356 _M. F. Hasler_, Jun 03 2009