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A022842
Beatty sequence for sqrt(8).
21
2, 5, 8, 11, 14, 16, 19, 22, 25, 28, 31, 33, 36, 39, 42, 45, 48, 50, 53, 56, 59, 62, 65, 67, 70, 73, 76, 79, 82, 84, 87, 90, 93, 96, 98, 101, 104, 107, 110, 113, 115, 118, 121, 124, 127, 130, 132, 135, 138, 141, 144, 147, 149, 152, 155, 158, 161, 164
OFFSET
1,1
FORMULA
a(n) = floor(2*n*sqrt(2)). - Michel Marcus, Oct 31 2017
MAPLE
a:=n->floor(2*n*sqrt(2)): seq(a(n), n=1..60); # Muniru A Asiru, Sep 28 2018
MATHEMATICA
Table[Floor[2*n*Sqrt[2]], {n, 1, 60}] (* G. C. Greubel, Sep 28 2018 *)
PROG
(Magma) [Floor(n*Sqrt(8)): n in [1..60]]; // Vincenzo Librandi, Oct 24 2011
(PARI) vector(80, n, floor(2*n*sqrt(2))) \\ G. C. Greubel, Sep 28 2018
(Python)
from sympy import integer_nthroot
def A022842(n): return integer_nthroot(8*n**2, 2)[0] # Chai Wah Wu, Mar 16 2021
CROSSREFS
A bisection of A001951. Cf. A010466.
Sequence in context: A282457 A329848 A059560 * A356057 A189525 A189369
KEYWORD
nonn,easy
EXTENSIONS
Offset changed from 0 to 1 by Vincenzo Librandi, Oct 24 2011
STATUS
approved