A187967 a(n) = floor((n+k)*r) - floor(n*r) - floor(k*r), where r=sqrt(2), k=2.

1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0

Offset

1

Comments

See A187950.

Links

G. C. Greubel, Table of n, a(n) for n = 1..20000

Mathematica

(* First program *)
r=2^(1/2); k=2;
seqA=Table[Floor[(n+2)r]-Floor[n*r]-Floor[k*r], {n, 1, 220}]  (* this sequence *)
Flatten[Position[seqA, 0]]  (* A098021 conjectured *)
Flatten[Position[seqA, 1]]  (* A187968 *)
(* Alternative: *)
Table[Floor[n Sqrt[2]+2Sqrt[2]]-Floor[n Sqrt[2]]-Floor[2Sqrt[2]], {n, 150}] (* Harvey P. Dale, Mar 23 2025 *)

Prog

(Magma)
A187967:= func< n | Floor((n+2)*Sqrt(2)) -Floor(n*Sqrt(2)) -Floor(2*Sqrt(2)) >;
[A187967(n): n in [1..150]]; // G. C. Greubel, Nov 06 2025
(SageMath)
def A187967(n): return floor((n+2)*sqrt(2)) -floor(n*sqrt(2)) -floor(2*sqrt(2))
print([A187967(n) for n in range(1, 151)]) # G. C. Greubel, Nov 06 2025

Crossrefs

Cf. A098021, A187950, A187968.

Sequence in context: A132342 A156174 A358847 * A106467 A106468 A030317

Adjacent sequences: A187964 A187965 A187966 * A187968 A187969 A187970

Keyword

nonn

Author

Clark Kimberling, Mar 17 2011

Status

approved