A194388 Numbers m such that Sum_{k=1..m} (<1/2 + k*r> - ) = 0, where r=sqrt(11) and < > denotes fractional part.

2, 4, 14, 16, 18, 22, 24, 26, 30, 32, 34, 44, 46, 48, 52, 54, 56, 60, 62, 64, 74, 76, 78, 82, 84, 86, 90, 92, 94, 104, 106, 108, 112, 114, 116, 120, 122, 124, 134, 136, 138, 142, 144, 146, 150, 152, 154, 164, 166, 168, 172, 174, 176, 180, 182, 184, 194, 196

Offset: 1

Author

Clark Kimberling, Aug 23 2011

Keywords

• nonn

Comments

Every term is even; see A194368.

Crossrefs

Cf. A010468, A194368, A194387, A194389.

Programs

Mathematica

r = Sqrt[11]; c = 1/2;
x[n_] := Sum[FractionalPart[k*r], {k, 1, n}]
y[n_] := Sum[FractionalPart[c + k*r], {k, 1, n}]
t1 = Table[If[y[n] < x[n], 1, 0], {n, 1, 200}];
Flatten[Position[t1, 1]]     (* A194387 *)
t2 = Table[If[y[n] == x[n], 1, 0], {n, 1, 200}];
Flatten[Position[t2, 1]]     (* A194388 *)
t3 = Table[If[y[n] > x[n], 1, 0], {n, 1, 200}];
Flatten[Position[t3, 1]]     (* A194389 *)