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A094386
a(n) = floor(sqrt(3)*2^(n-1)).
6
1, 3, 6, 13, 27, 55, 110, 221, 443, 886, 1773, 3547, 7094, 14188, 28377, 56755, 113511, 227023, 454046, 908093, 1816186, 3632373, 7264747, 14529495, 29058990, 58117981, 116235962, 232471924, 464943848, 929887696, 1859775393, 3719550786
OFFSET
1,2
LINKS
FORMULA
a(n) = A022838(2^(n-1)). - R. J. Mathar, Oct 22 2011
MATHEMATICA
Table[Floor[Sqrt[3] 2^(n-1)], {n, 40}] (* Vincenzo Librandi, Sep 20 2017 *)
PROG
(Magma) [Floor(2^(n-1)*Sqrt(3)): n in [1..40]]; // Vincenzo Librandi, Sep 20 2017
(PARI) a(n) = floor(sqrt(3)*2^(n-1)); \\ Michel Marcus, Sep 20 2017
(Python)
from math import isqrt
def A094386(n): return isqrt(3*(1<<(n-1<<1))) # Chai Wah Wu, Jul 28 2022
CROSSREFS
Sequence in context: A065830 A055143 A092539 * A371902 A267604 A099036
KEYWORD
nonn
AUTHOR
Roger L. Bagula, Jun 03 2004
STATUS
approved