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%I #12 Dec 06 2019 15:50:46
%S 5,7,9,11,18,20,22,24,31,33,35,37,44,46,48,50,57,59,61,63,68,70,72,74,
%T 76,81,83,85,87,94,96,98,100,107,109,111,113,120,122,124,126,133,135,
%U 137,139,146,148,150,152,157,159,161,163,165,170,172,174,176,183
%N Numbers k such that L(k) = 2 mod 3, where L = A000201 = lower Wythoff sequence.
%C The sequences A283769, A283770, A283771 partition the positive integers.
%H Clark Kimberling, <a href="/A283771/b283771.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n+1) - a(n) is in {2,5,7} for every n.
%t r = GoldenRatio; z = 350; t = Table[Floor[n*r], {n, 1, z}]; u = Mod[t, 3];
%t Flatten[Position[u, 0]] (* A283769 *)
%t Flatten[Position[u, 1]] (* A283770 *)
%t Flatten[Position[u, 2]] (* A283771 *)
%o (PARI) r = (1 + sqrt(5))/2;
%o for(n=1, 351, if(floor(n*r)%3==2, print1(n,", "))) \\ _Indranil Ghosh_, Mar 19 2017
%o (Python)
%o import math
%o from sympy import sqrt
%o r = (1 + sqrt(5))/2
%o [n for n in range(1, 351) if int(math.floor(n*r))%3==2] # _Indranil Ghosh_, Mar 19 2017
%Y Cf. A000201, A001622, A283769, A283770.
%K nonn,easy
%O 1,1
%A _Clark Kimberling_, Mar 18 2017
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