A187946 [nr+kr]-[nr]-[kr], where r=(1+sqrt(5))/2, k=5, [ ]=floor.

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

Offset

1

Comments

See A187950.

Links

Chai Wah Wu, Table of n, a(n) for n = 1..10000

Formula

a(n)=[nr+5r]-[nr]-[5r], where r=(1+sqrt(5))/2.

Mathematica

r=(1+5^(1/2))/2;
seqA=Table[Floor[(n+5)r]-Floor[n*r]-8, {n, 1, 220}]   (* A187946 *)
Flatten[Position[seqA, 0] ]   (* A187947 *)
Flatten[Position[seqA, 1] ]   (* A134862 *)

Prog

(Python)
from __future__ import division
from gmpy2 import isqrt
def A187946(n):
    return int((isqrt(5*(n+5)**2)+n+1)//2 -(isqrt(5*n**2)+n)//2 - 6) # Chai Wah Wu, Oct 08 2016

Crossrefs

Cf. A187950, A187947, A134862.

Sequence in context: A366124 A295662 A367512 * A330549 A342019 A323510

Adjacent sequences: A187943 A187944 A187945 * A187947 A187948 A187949

Keyword

nonn

Author

Clark Kimberling, Mar 16 2011

Status

approved