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A190081 n + [n*r/t] + [n*s/t];  r=1, s=cos(Pi/5), t=sec(Pi/5). 3
1, 4, 6, 9, 12, 13, 16, 19, 21, 24, 26, 28, 31, 34, 36, 38, 41, 43, 46, 49, 50, 53, 56, 58, 61, 64, 65, 68, 70, 73, 76, 77, 80, 83, 85, 88, 90, 92, 95, 98, 100, 102, 105, 107, 110, 113, 115, 117, 120, 122, 125, 128, 129, 132, 134, 137, 140, 141, 144, 147, 149, 152, 154, 156, 159, 162, 164, 167, 169, 171, 174, 177, 179, 181, 184 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

See A190079.

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = n + [n*cos(Pi/5)] + [n*(cos(Pi/5))^2].

MATHEMATICA

r=1; s=Cos[Pi/5]; t=Sec[Pi/5];

a[n_] := n + Floor[n*s/r] + Floor[n*t/r];

b[n_] := n + Floor[n*r/s] + Floor[n*t/s];

c[n_] := n + Floor[n*r/t] + Floor[n*s/t];

Table[a[n], {n, 1, 120}]  (*A190079*)

Table[b[n], {n, 1, 120}]  (*A190080*)

Table[c[n], {n, 1, 120}]  (*A190081*)

PROG

(PARI) for(n=1, 100, print1(n + floor(n*cos(Pi/5)) + floor(n*(cos(Pi/5))^2), ", ")) \\ G. C. Greubel, Feb 15 2018

(MAGMA) R:= RealField(); [n + Floor(n*Cos(Pi(R)/5)) + Floor(n*(Cos(Pi(R)/5))^2): n in [1..100]]; // G. C. Greubel, Feb 15 2018

CROSSREFS

Cf. A190079, A190080.

Sequence in context: A219612 A258743 A292660 * A298468 A190304 A189366

Adjacent sequences:  A190078 A190079 A190080 * A190082 A190083 A190084

KEYWORD

nonn

AUTHOR

Clark Kimberling, May 04 2011

STATUS

approved

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Last modified May 13 08:08 EDT 2021. Contains 343836 sequences. (Running on oeis4.)