A195171 a(n) = 5*n - floor(n*r), where r=(1+sqrt(5))/2 (the golden ratio).

0, 4, 7, 11, 14, 17, 21, 24, 28, 31, 34, 38, 41, 44, 48, 51, 55, 58, 61, 65, 68, 72, 75, 78, 82, 85, 88, 92, 95, 99, 102, 105, 109, 112, 115, 119, 122, 126, 129, 132, 136, 139, 143, 146, 149, 153, 156, 159, 163, 166, 170, 173, 176, 180, 183, 187, 190, 193

Offset

0,2

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..10000

Formula

a(n) = 5*n - A000201(n) = n + A195170(n). - R. J. Mathar, Sep 11 2011

Mathematica

With[{c = GoldenRatio}, Table[5*n - Floor[c*n], {n, 0, 50}]] (* G. C. Greubel, Oct 31 2017 *)

Prog

(Magma) [5*n-Floor(n*(1+Sqrt(5))/2): n in [0..70]]; // Vincenzo Librandi, Sep 11 2011
(PARI) for(n=0, 50, print1(5*n - floor(n*(1+sqrt(5))/2), ", ")) \\ G. C. Greubel, Oct 31 2017
(Python)
from math import isqrt
def A195171(n): return (m:=5*n)-(n+isqrt(n*m)>>1) # Chai Wah Wu, Aug 10 2022

Crossrefs

Sequence in context: A327737 A081834 A078309 * A184623 A184581 A310725

Adjacent sequences: A195168 A195169 A195170 * A195172 A195173 A195174

Keyword

nonn

Author

Clark Kimberling, Sep 10 2011

Status

approved