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 A095259 #9 Dec 31 2014 17:42:05 %S A095259 1,3,2,4,10,5,21,9,6,16,18,14,19,39,25,26,11,8,51,38,46,56,20,15,17, %T A095259 34,7,48,50,37,78,27,67,12,52,33,64,66,69,44,169,53,134,93,95,40,22, %U A095259 28,47,41,29,89,91,54,96,60,70,99,312,43,202,80,157,55,63,92,130,13 %N A095259 Smallest m such that A095258(m) = n. %C A095259 Inverse of A095258, if the conjecture is true, that this is a permutation: a(A095258(n)) = A095258(a(n)) = n; %C A095259 A095261(n) = a(a(n)). %H A095259 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %o A095259 (Haskell) %o A095259 import Data.List (elemIndex); import Data.Maybe (fromJust) %o A095259 a095259 = (+ 1) . fromJust . (`elemIndex` a095258_list) %o A095259 -- _Reinhard Zumkeller_, Dec 31 2014 %K A095259 nonn %O A095259 1,2 %A A095259 _Reinhard Zumkeller_, May 31 2004 %E A095259 Revised version: _Reinhard Zumkeller_, Dec 31 2014