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A335137 a(n) = floor(n*Im(2*e^(i*Pi/5))). 2

%I

%S 1,2,3,4,5,7,8,9,10,11,12,14,15,16,17,18,19,21,22,23,24,25,27,28,29,

%T 30,31,32,34,35,36,37,38,39,41,42,43,44,45,47,48,49,50,51,52,54,55,56,

%U 57,58,59,61,62,63,64,65,67,68,69,70,71,72

%N a(n) = floor(n*Im(2*e^(i*Pi/5))).

%C This is the Beatty sequence for imaginary part of 2*e^(i*Pi/5).

%C Im(2*e^(i*Pi/5)) = A182007 = 1.1755705045849462583374119... = 2*sin(Pi/5).

%C The real part of floor(n*2*e^(i*Pi/5)) is A000201 (floor(n*phi)).

%C Re(2*e^(i*Pi/5)) = A001622 = phi = (1 + sqrt(5))/2.

%C For n < 57, a(n) = A109234(n).

%H Karl V. Keller, Jr., <a href="/A335137/b335137.txt">Table of n, a(n) for n = 1..10000</a>

%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/BeattySequence.html">BeattySequence</a>.

%H <a href="/index/Be#Beatty">Index entries for sequences related to Beatty sequences</a>

%e For n = 3, floor(3*1.17557) = 3.

%t Array[Floor[# Im[2 E^(I*Pi/5)]] &, 62] (* _Michael De Vlieger_, May 24 2020 *)

%o (Python)

%o from sympy import floor, im, exp, I, pi

%o for n in range(1, 101): print(floor(n*im(2*exp(I*pi/5))), end=', ')

%Y Cf. A000201, A001622, A109234, A182007.

%K nonn

%O 1,2

%A _Karl V. Keller, Jr._, May 24 2020

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Last modified August 8 14:36 EDT 2020. Contains 336298 sequences. (Running on oeis4.)