A194979 a(n) = 1 + floor(n/sqrt(3)).

1, 2, 2, 3, 3, 4, 5, 5, 6, 6, 7, 7, 8, 9, 9, 10, 10, 11, 11, 12, 13, 13, 14, 14, 15, 16, 16, 17, 17, 18, 18, 19, 20, 20, 21, 21, 22, 22, 23, 24, 24, 25, 25, 26, 26, 27, 28, 28, 29, 29, 30, 31, 31, 32, 32, 33, 33, 34, 35, 35, 36, 36, 37, 37, 38, 39, 39, 40, 40, 41, 41

Offset: 1

Author

Clark Kimberling, Sep 07 2011

Keywords

• nonn
• easy

Comments

The fractalization of this sequence is A194980.

Least number k such that k*tan(1/k) - 1 < 1/n^2. - Clark Kimberling, Dec 02 2014

The integers k such that a(k) = a(k+1) give A054406. - Michel Marcus, Nov 01 2021

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A054406, A097337, A194980, A194981.

Programs

Magma

[1+Floor(n/Sqrt(3)): n in [1..80] ];// Vincenzo Librandi, Sep 10 2011

Mathematica

p[n_]:=1+Floor[n/Sqrt[3]]
Table[p[n],{n,1,90}] (* A194979 *)

PARI

a(n)=1+sqrtint(n^2\3) \\ Charles R Greathouse IV, Sep 02 2015

Formula

a(n) = 1 + A097337(n).