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A293314
Least integer k such that k/2^n > (1+sqrt(5))/2 (the golden ratio).
4
2, 4, 7, 13, 26, 52, 104, 208, 415, 829, 1657, 3314, 6628, 13255, 26510, 53020, 106040, 212079, 424158, 848316, 1696632, 3393264, 6786527, 13573053, 27146106, 54292212, 108584423, 217168846, 434337692, 868675384, 1737350767, 3474701533, 6949403066
OFFSET
0,1
LINKS
FORMULA
a(n) = ceiling(r*2^n), where r = (1+sqrt(5))/2.
a(n) = A293313(n) + 1.
MAPLE
A293314:=n->ceil(2^n*(1+sqrt(5))/2): seq(A293314(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) = ceil(2^n*(1+sqrt(5))/2) \\ Altug Alkan, Oct 06 2017
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Clark Kimberling, Oct 06 2017
STATUS
approved