cp's OEIS Frontend

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.

A164287 Sequence resulting from an infinite series of reordering steps applied to the sequence of natural numbers A000027: At step n number n is moved from its position p to position p+k, where k is the actual number at position p+1.

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%I A164287 #19 Dec 21 2021 23:26:35
%S A164287 1,3,2,4,5,8,6,7,9,12,13,10,11,16,14,17,18,15,20,24,19,25,21,22,23,31,
%T A164287 26,34,27,33,28,37,29,38,36,30,39,32,35,46,44,47,40,48,41,42,43,49,50,
%U A164287 53,45,58,51,59,61,52,67,54,68,55,69,56,70,57,60,73,62,63,64,65,66,80
%N A164287 Sequence resulting from an infinite series of reordering steps applied to the sequence of natural numbers A000027: At step n number n is moved from its position p to position p+k, where k is the actual number at position p+1.
%C A164287 This sequence is a permutation of the natural numbers.
%H A164287 Alois P. Heinz <a href="/A164287/b164287.txt">Table of n, a(n) for n = 1..10000</a>
%H A164287 Eric Angelini, <a href="http://www.cetteadressecomportecinquantesignes.com/ColourReadJump.htm">Colour, read and jump sequence</a>
%H A164287 E. Angelini, <a href="/A164286/a164286.pdf">Colour, drag and drop sequence</a> [Cached copy, with permission]
%H A164287 E. Angelini, <a href="/A164287/a164287.pdf">Color, read and jump sequence</a> [Cached copy, with permission]
%p A164287 mx:= 620: # increase mx to get more items
%p A164287 l:= [i$i=1..2*mx]: pos:= proc(n) global l; local i; for i to nops(l) while l[i]<>n do od; `if`(i>nops(l), -1, i) end: for n from 1 to mx do p:= pos(n); k:= l[p+1]; l:= [l[1..p-1][], l[p+1..p+k][], l[p], l[p+k+1..nops(l)][]] od: p:= pos(mx+1): a:= n-> `if`(n<p, l[n], NULL): seq(a(n), n=1..p);
%t A164287 max = 200; r = Range[max]; For[n = 1, True, n++, p = Position[r, n]; If[p == {} || (q = p[[1, 1]] + r[[p[[1, 1]] + 1]] + 1) > max, Break[], c = r[[q]]; r = r /. {a___, n, b___, c, d___} :> {a, b, n, c, d}]]; A164287 = r[[1 ;; 72]] (* _Jean-François Alcover_, Jun 14 2012 *)
%Y A164287 Cf. A164286.
%K A164287 nice,nonn,look
%O A164287 1,2
%A A164287 _Eric Angelini_ and _Alois P. Heinz_, Aug 12 2009