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%I #14 Mar 18 2022 21:51:16
%S 1,2,4,3,5,6,8,7,10,9,14,12,11,13,18,16,15,20,26,22,21,17,19,24,23,25,
%T 28,27,29,38,32,31,33,36,40,30,39,35,34,44,37,43,45,41,50,47,49,42,52,
%U 46,56,48,58,51,66,53,55,54,59,61,57,64,60,63,67,78,68,62,70,65,77,75
%N Permutation of natural numbers, inverse permutation to A094870.
%C 2n/3 < a(n) <= 8n/3 (P. Hegarty).
%C Conjecture: lim_{n->infinity} a(n)/n = 1 (P. Hegarty).
%H Carl R. White, <a href="/A095689/b095689.txt">Table of n, a(n) for n = 1..9660</a>
%H Peter Hegarty, <a href="https://doi.org/10.37236/1792">Permutations avoiding arithmetic patterns</a>, The Electronic Journal of Combinatorics, 11 (2004), #R39.
%e a(3)=4 because A094870(4)=3.
%p A:=proc(n) option remember; local t, S, i; S:={$1..300} minus {seq(A(i),i=1..n-1)}; t:=min(S[]); i:=1; while i<floor((n+1)/2) do if t-A(n-i)=A(n-i)-A(n-2*i) then S:=S minus {t}; t:=min(S[]); i:=1 else i:=i+1 fi od; t end: A(1):=1: L:=[seq(A(n),n=1..200)]: a:=n-> if member(n,L,'p') then p else 0 fi: seq(a(n),n=1..194);
%Y Cf. A094870.
%K easy,nonn
%O 1,2
%A Alec Mihailovs (alec(AT)mihailovs.com), Jul 05 2004
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