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A252169
Beatty sequence for sqrt(Pi*phi) where phi is the golden ratio A001622.
2
2, 4, 6, 9, 11, 13, 15, 18, 20, 22, 24, 27, 29, 31, 33, 36, 38, 40, 42, 45, 47, 49, 51, 54, 56, 58, 60, 63, 65, 67, 69, 72, 74, 76, 78, 81, 83, 85, 87, 90, 92, 94, 96, 99, 101, 103, 105, 108, 110, 112, 114, 117, 119, 121, 124, 126, 128, 130
OFFSET
1,1
LINKS
Eric Weisstein's World of Mathematics, Beatty Sequence.
Eric Weisstein's World of Mathematics, Golden Ratio
Eric Weisstein's World of Mathematics, Pi
FORMULA
a(n) = floor(n*sqrt(Pi*phi)) = floor(n*sqrt(Pi*(1+sqrt(5))/2)).
EXAMPLE
For n = 5, floor(5*sqrt(Pi*(1+sqrt(5))/2)) = 11.
MATHEMATICA
a252169[n_] := Floor[#*Sqrt[Pi*((1 + Sqrt[5])/2)]] & /@ Range@n; a252169[58] (* Michael De Vlieger, Dec 27 2014 *)
PROG
(Python) from sympy import *
for n in range(1, 3001): print(floor(n*sqrt(pi*(1+sqrt(5))/2)), end=', ')
(PARI) vector(100, n, floor(n*sqrt(Pi*(1+sqrt(5))/2))) \\ Derek Orr, Dec 30 2014
CROSSREFS
Cf. A000796 (Pi), A001622 (golden ratio, phi), A094886 (Pi*phi).
Cf. A253301 (complement).
Sequence in context: A248898 A207188 A085148 * A187842 A330000 A059566
KEYWORD
nonn,easy
AUTHOR
Karl V. Keller, Jr., Dec 15 2014
STATUS
approved