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

1,1

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]

Mathematica

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

Prog

(Magma) [Floor(24*(2^n-1)/n): n in [1..45]]; // Vincenzo Librandi, May 08 2011
(Python)
def A003176(n): return ((3<<n+3)-24)//n # Chai Wah Wu, Aug 24 2023

Crossrefs

Cf. A000799, A003138, A003177, A121056.

Sequence in context: A165602 A124283 A143645 * A003138 A003177 A038530

Adjacent sequences: A003173 A003174 A003175 * A003177 A003178 A003179

Keyword

nonn

Author

N. J. A. Sloane

Status

approved