%I #8 Aug 01 2019 10:48:05
%S 1,2,2,3,4,4,5,6,6,7,7,8,9,9,10,10,11,11,12,13,13,13,14,14,15,16,16,
%T 17,17,18,19,19,19,20,20,21,21,22,23,23,24,24,25,25,26,26,26,27,27,28,
%U 29,29,30,30,31,31,32,33,33,33,34,34,35,36,36,37,37,38,38,38,39,39,40,41,41,41,42,42,43,44,44
%N a(n) = a(n-a(n-1)) + a(n-a(n-4)), with a(n) = ceiling(2*n/3) for n <= 7.
%C A slow solution to Hofstadter V recurrence.
%C Numbers k such that a(k) < A063882(k) are 1654, 1721, 1925, ...
%F a(n+1) - a(n) = 0 or 1 for all n >= 1.
%o (PARI) q=vector(100); for(n=1, 7, q[n]=ceil(2*n/3));for(n=8, #q, q[n]=q[n-q[n-1]] +q[n-q[n-4]]); q
%Y Cf. A063882, A317686, A319020.
%K nonn,easy
%O 1,2
%A _Altug Alkan_, Aug 01 2019
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