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A190486 Positions of 2 in A190483.

%I A190486 #18 Mar 12 2021 07:51:39
%S A190486 2,7,12,14,19,24,31,36,41,43,48,53,60,65,70,72,77,82,84,89,94,101,106,
%T A190486 111,113,118,123,130,135,140,142,147,152,159,164,171,176,181,183,188,
%U A190486 193,200,205,210,212,217,222,229,234,239,241,246,251,253,258,263,270,275,280,282,287,292,299,304,309,311,316
%N A190486 Positions of 2 in A190483.
%C A190486 See A190483.
%H A190486 G. C. Greubel, <a href="/A190486/b190486.txt">Table of n, a(n) for n = 1..1000</a>
%t A190486 r = Sqrt[2]; b = 2; c = 1;
%t A190486 f[n_] := Floor[(b*n + c)*r] - b*Floor[n*r] - Floor[c*r];
%t A190486 t = Table[f[n], {n, 1, 200}]  (* A190483 *)
%t A190486 Flatten[Position[t, 0]]   (* A190484 *)
%t A190486 Flatten[Position[t, 1]]   (* A190485 *)
%t A190486 Flatten[Position[t, 2]]   (* A190486 *)
%o A190486 (Python)
%o A190486 from sympy import sqrt, floor
%o A190486 r=sqrt(2)
%o A190486 def a190483(n): return floor((2*n + 1)*r) - 2*floor(n*r) - floor(r)
%o A190486 print([n for n in range(1, 501) if a190483(n)==2]) # _Indranil Ghosh_, Jul 02 2017
%Y A190486 Cf. A190483, A190484, A190485.
%K A190486 nonn
%O A190486 1,1
%A A190486 _Clark Kimberling_, May 11 2011