A190081 n + [n*r/t] + [n*s/t]; r=1, s=cos(Pi/5), t=sec(Pi/5).

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

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 * A364445 A298468 A190304

Adjacent sequences: A190078 A190079 A190080 * A190082 A190083 A190084

Keyword

nonn

Author

Clark Kimberling, May 04 2011

Status

approved