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A293313
Greatest integer k such that k/2^n < (1+sqrt(5))/2 (the golden ratio).
9
1, 3, 6, 12, 25, 51, 103, 207, 414, 828, 1656, 3313, 6627, 13254, 26509, 53019, 106039, 212078, 424157, 848315, 1696631, 3393263, 6786526, 13573052, 27146105, 54292211, 108584422, 217168845, 434337691, 868675383, 1737350766, 3474701532, 6949403065
OFFSET
0,2
LINKS
FORMULA
a(n) = floor(r*2^n), where r = (1+sqrt(5))/2.
a(n) = A293314(n) - 1.
MAPLE
A293313:=n->floor(2^n*(1+sqrt(5))/2): seq(A293313(n), n=0..40); # Wesley Ivan Hurt, Oct 06 2017
MATHEMATICA
z = 120; r = GoldenRatio;
Table[Floor[r*2^n], {n, 0, z}]; (* A293313 *)
Table[Ceiling[r*2^n], {n, 0, z}]; (* A293314 *)
Table[Round[r*2^n], {n, 0, z}]; (* A293315 *)
PROG
(PARI) a(n) = (2^n*(1+sqrt(5)))\2; \\ Altug Alkan, Oct 06 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Oct 06 2017
STATUS
approved