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[nr+kr]-[nr]-[kr], where r=1/sqrt(2), k=2, [ ]=floor.
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%I #11 Oct 08 2016 16:58:32

%S 1,0,0,1,0,0,1,1,0,0,1,0,0,1,1,0,0,1,0,0,1,0,0,1,1,0,0,1,0,0,1,1,0,0,

%T 1,0,0,1,0,0,1,1,0,0,1,0,0,1,1,0,0,1,0,0,1,1,0,0,1,0,0,1,0,0,1,1,0,0,

%U 1,0,0,1,1,0,0,1,0,0,1,0,0,1,1,0,0,1,0,0,1,1,0,0,1,0,0,1,1,0,0,1,0,0,1,0,0,1,1,0,0,1,0,0,1,1,0,0,1,0,0,1,0,0,1,1,0,0,1,0,0,1,1,0,0,1,0,0,1,0,0,1,1,0,0,1,0,0,1,1,0,0,1,0,0,1,1

%N [nr+kr]-[nr]-[kr], where r=1/sqrt(2), k=2, [ ]=floor.

%C See A187950. For k=1 instead of 2, see A080764 for which the position sequences of 0 and 1 are A001952 and A001951, respectively.

%H Chai Wah Wu, <a href="/A188374/b188374.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n)=[nr+2r]-[nr]-[2r], where r=1/sqrt(2).

%t r=2^(-1/2); k=2;

%t t=Table[Floor[n*r+k*r]-Floor[n*r]-Floor[k*r], {n,1,220}] (* A188374 *)

%t Flatten[Position[t,0] ] (* A188375 *)

%t Flatten[Position[t,1] ] (* A188376 *)

%o (Python)

%o from __future__ import division

%o from gmpy2 import isqrt

%o def A188374(n):

%o return int(isqrt((n+2)**2//2)-isqrt(n**2//2)) - 1 # _Chai Wah Wu_, Oct 08 2016

%Y Cf. A187950, A188375, A188376, A080764.

%K nonn

%O 1

%A _Clark Kimberling_, Mar 29 2011