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.

A164286 Sequence resulting from an infinite series of reordering steps applied to the sequence of natural numbers A000027: At step n, when number n is at position p, the number k at position p+n is moved to position p+1.

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%I A164286 #11 Jun 09 2016 21:48:36
%S A164286 1,2,4,6,9,11,15,17,20,25,27,29,33,36,40,42,46,49,51,54,60,63,65,68,
%T A164286 70,75,77,82,85,89,92,94,97,101,103,106,110,113,115,118,125,127,132,
%U A164286 134,136,140,143,146,148,153,157,159,162,165,169,173,178,180,182,186,189
%N A164286 Sequence resulting from an infinite series of reordering steps applied to the sequence of natural numbers A000027: At step n, when number n is at position p, the number k at position p+n is moved to position p+1.
%C A164286 It seems that a(n)/n > 3 for all n > 40.
%C A164286 This sequence is not a permutation of the natural numbers.
%H A164286 Alois P. Heinz <a href="/A164286/b164286.txt">Table of n, a(n) for n = 1..5000</a>
%H A164286 Eric Angelini, <a href="http://www.cetteadressecomportecinquantesignes.com/ColourDragDrop.htm">Colour, drag and drop sequence</a>
%H A164286 E. Angelini, <a href="/A164286/a164286.pdf">Colour, drag and drop sequence</a> [Cached copy, with permission]
%p A164286 mx:= 300: # increase mx to get more items
%p A164286 l:= [i$i=1..3*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); l:= [l[1..p][], l[n+p], l[p+1..n+p-1][], l[n+p+1..nops(l)][]] od: for p to nops(l) do if l[p]>=mx then break fi od: a:= n-> `if`(n<p, l[n], NULL): seq(a(n), n=1..p);
%t A164286 max = 900; r = Range[max]; For[n = 1, True, n++, p = Position[r, n]; If[p == {} || p[[1, 1]] + n > max, Break[], c = r[[p[[1, 1]] + n]]; r = r /. {a___, n, b___, c, d___} :> {a, n, c, b, d}]]; A164286 = r[[1 ;; 61]] (* _Jean-François Alcover_, Jun 14 2012 *)
%Y A164286 Cf. A164287.
%K A164286 nice,nonn
%O A164286 1,2
%A A164286 _Eric Angelini_ and _Alois P. Heinz_, Aug 12 2009