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A284523 a(1) = a(2) = 1, a(3) = 2; a(n) = a(a(n-1)-1) + a(n-a(n-3)-1) for n > 3. 4

%I #12 May 08 2017 12:31:04

%S 1,1,2,2,3,3,3,3,4,5,5,5,5,5,6,8,8,8,8,8,8,8,8,9,11,13,13,13,11,13,13,

%T 13,13,13,13,13,13,14,16,19,21,19,16,14,16,17,21,21,21,21,19,21,21,21,

%U 21,21,21,21,21,22,24,27,32,29,26,24,21,29,27,34,34,27,27,29,34,34,34,29,27,29,32

%N a(1) = a(2) = 1, a(3) = 2; a(n) = a(a(n-1)-1) + a(n-a(n-3)-1) for n > 3.

%H Robert Israel, <a href="/A284523/b284523.txt">Table of n, a(n) for n = 1..10000</a>

%H Altug Alkan, <a href="/A284523/a284523.png">Plot for n=0..10^6</a>

%p a:= proc(n) option remember;

%p procname(procname(n-1)-1) + procname(n-procname(n-3)-1)

%p end proc:

%p a(1):= 1: a(2):= 1: a(3):= 2:

%p map(a, [$1..100]);

%t a[1] = a[2] = 1; a[3] = 2; a[n_] := a[n] = a[a[n - 1] - 1] + a[n - a[n - 3] - 1]; Array[a, 81] (* _Michael De Vlieger_, Mar 28 2017 *)

%Y Cf. A004001, A005185, A055748.

%K nonn,look

%O 1,3

%A _Altug Alkan_ and _Robert Israel_, Mar 28 2017

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Last modified April 24 14:09 EDT 2024. Contains 371960 sequences. (Running on oeis4.)