A003176 Integer part of 24(2^n-1)/n.

24, 36, 56, 90, 148, 252, 435, 765, 1362, 2455, 4466, 8190, 15121, 28085, 52427, 98302, 185041, 349524, 662257, 1258290, 2396744, 4575603, 8753329, 16777215, 32212253, 61946642, 119304646, 230087532

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn

Links

• Vincenzo Librandi, Table of n, a(n) for n = 1..300
• R. J. Penrose, Puzzle, Twistor Newsletter, No. 10 (July 1980), p. 22.
• R. J. Penrose, Puzzle, Twistor Newsletter, No. 10 (July 1980), p. 22. [Cached copy]
• R. J. Penrose, Solution to puzzle, Twistor Newsletter, No. 41, p. 37, 1996.
• R. J. Penrose, Solution to puzzle, Twistor Newsletter, No. 41, p. 37, 1996. [Cached copy]

Crossrefs

Cf. A000799, A003138, A003177, A121056.

Programs

Magma

[Floor(24*(2^n-1)/n): n in [1..45]]; // Vincenzo Librandi, May 08 2011

Mathematica

a[n_] := Floor[24*(2^n-1)/n]; Array[a, 30] (* Giovanni Resta, Mar 25 2017 *)

Python

def A003176(n): return ((3<Chai Wah Wu, Aug 24 2023