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A188090
[nr+kr]-[nr]-[kr], where r=sqrt(3), k=5, [ ]=floor.
3
1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 1, 1
OFFSET
1
COMMENTS
See A187950.
FORMULA
a(n)=[nr+5r]-[nr]-[5r], where r=sqrt(3).
MATHEMATICA
r=3^(1/2); k=5;
seqA=Table[Floor[n*r+k*r]-Floor[n*r]-Floor[k*r], {n, 1, 220}] (* A188090 *)
Flatten[Position[seqA, 0] ] (* A188091 *)
Flatten[Position[seqA, 1] ] (* A188092 *)
PROG
(Python)
from gmpy2 import isqrt
def A188090(n):
return int(isqrt(3*(n+5)**2)-isqrt(3*n**2)) - 8 # Chai Wah Wu, Oct 08 2016
CROSSREFS
KEYWORD
nonn
AUTHOR
Clark Kimberling, Mar 20 2011
STATUS
approved