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A334415
Nearest integer to n*(2-phi), where phi is the golden ratio (A001622).
2
0, 0, 1, 1, 2, 2, 2, 3, 3, 3, 4, 4, 5, 5, 5, 6, 6, 6, 7, 7, 8, 8, 8, 9, 9, 10, 10, 10, 11, 11, 11, 12, 12, 13, 13, 13, 14, 14, 15, 15, 15, 16, 16, 16, 17, 17, 18, 18, 18, 19, 19, 19, 20, 20, 21, 21, 21, 22, 22, 23, 23, 23, 24, 24, 24, 25, 25, 26, 26, 26, 27, 27
OFFSET
0,5
FORMULA
a(n) = round(n*(2-phi)).
a(n) = n - A101803(n).
EXAMPLE
a(0) = round(0*(2-phi)) = round(0) = 0.
a(1) = round(1*(2-phi)) = round(0.382) = 0.
a(2) = round(2*(2-phi)) = round(0.764) = 1.
MATHEMATICA
a[n_] := Round[n * (2 - GoldenRatio)]; Array[a, 72, 0] (* Amiram Eldar, Jun 14 2020 *)
PROG
(PARI) a(n) = round(n*(2-(1+sqrt(5))/2)); \\ Michel Marcus, Jun 14 2020
CROSSREFS
Sequence in context: A026405 A226033 A054404 * A307152 A008671 A199017
KEYWORD
nonn
AUTHOR
Aresh Pourkavoos, Apr 30 2020
STATUS
approved