A283893 - OEIS

%I #4 Mar 19 2017 19:25:51

%S 3,2,3,5,2,8,2,8,5,4,10,10,6,13,7,8,9,9,8,20,9,8,20,13,12,19,15,11,22,

%T 16,12,28,11,28,15,17,28,13,29,25,18,22,21,28,22,22,24,32,21,31,36,17,

%U 26,39,30,28,37,25,36,28,23,57,33,14,64,19,35,32,56,26,29,43,44,28,36

%N Relative of Hofstadter Q-sequence: a(1) = 3, a(2) = 2; thereafter a(n) = a(n-a(n-1)) + a(n-a(n-2)).

%C In calculating terms of this sequence, use the convention that a(n)=0 for n<=0.

%C Much like the Hofstadter Q-sequence A005185, it is not known if this sequence is defined for all positive n.

%C Empirically, this sequence appears to grow approximately like n/2 with a lot of noise.

%H Nathan Fox, <a href="/A283893/b283893.txt">Table of n, a(n) for n = 1..10000</a>

%p A283893:=proc(n) option remember: if n <= 0 then 0: elif n = 1 then 3: elif n = 2 then 2: else A283893(n-A283893(n-1)) + A283893(n-A283893(n-2)): fi: end:

%Y Cf. A005185, A278066, A278067, A278068, A283894, A283895, A283896, A283897.

%K nonn

%O 1,1

%A _Nathan Fox_, Mar 19 2017