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 A026262 #13 Feb 16 2025 08:32:35 %S A026262 2,1,4,3,6,5,8,7,11,13,9,15,10,17,12,20,14,22,24,16,26,18,29,19,31,21, %T A026262 33,35,23,38,25,40,27,42,28,44,46,30,49,32,51,34,53,36,55,37,58,60,39, %U A026262 62,41,64,43,67,45,69,71,47,73,48,76,50,78 %N A026262 Beginning with the natural numbers, swap [ k*sqrt(5) ] and [ (k/4)*(5 + sqrt(5)) ], for all k >= 1. %C A026262 Self-inverse integer permutation induced by Beatty sequences for sqrt(5) and (5+sqrt(5))/4. - _Reinhard Zumkeller_, Jun 11 2005 %H A026262 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/BeattySequence.html">Beatty Sequence</a> %H A026262 <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a> %H A026262 <a href="/index/Be#Beatty">Index entries for sequences related to Beatty sequences</a> %F A026262 a(A022839(n))=A108598(n) and a(A108598(n))=A022839(n). - _Reinhard Zumkeller_, Jun 11 2005 %Y A026262 Cf. A026250, A026255. %K A026262 nonn %O A026262 1,1 %A A026262 _Clark Kimberling_