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Numbers k such that Hofstadter Q-sequence Q(k) (A005185) satisfies Q(k) = k/2.
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%I #15 Jul 29 2021 01:01:54

%S 2,50,56,128,156,166,208,238,272,308,336,392,474,476,512,618,658,666,

%T 710,734,836,868,1016,1064,1376,1386,1424,1432,1832,2216,2280,2334,

%U 2606,2638,2676,2700,2740,2782,2786,2912,2922,2948,2954,3758

%N Numbers k such that Hofstadter Q-sequence Q(k) (A005185) satisfies Q(k) = k/2.

%F Conjecture: a(n)/n^2 is bounded. - _Benoit Cloitre_, Oct 26 2002

%t q[n_] := q[n] = If[n <= 2, 1, q[n - q[n-1]] + q[n - q[n-2]]];

%t Reap[For[n = 1, n <= 4000, n++, If[q[n] == n/2, Sow[n]]]][[2, 1]] (* _Jean-François Alcover_, Oct 02 2019 *)

%K nonn

%O 1,1

%A G. R. Bower (fsgrb(AT)aurora.alaska.edu)