A003176 - OEIS

%I #23 Aug 24 2023 12:01:45

%S 24,36,56,90,148,252,435,765,1362,2455,4466,8190,15121,28085,52427,

%T 98302,185041,349524,662257,1258290,2396744,4575603,8753329,16777215,

%U 32212253,61946642,119304646,230087532

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

%H Vincenzo Librandi, <a href="/A003176/b003176.txt">Table of n, a(n) for n = 1..300</a>

%H R. J. Penrose, <a href="http://people.maths.ox.ac.uk/lmason/Tn/TN1-25/No10%202%20July%201980.pdf">Puzzle</a>, Twistor Newsletter, No. 10 (July 1980), p. 22.

%H R. J. Penrose, <a href="/A003138/a003138.pdf">Puzzle</a>, Twistor Newsletter, No. 10 (July 1980), p. 22. [Cached copy]

%H R. J. Penrose, <a href="http://people.maths.ox.ac.uk/lmason/Tn/41/TN41.pdf">Solution to puzzle</a>, Twistor Newsletter, No. 41, p. 37, 1996.

%H R. J. Penrose, <a href="/A003138/a003138_1.pdf">Solution to puzzle</a>, Twistor Newsletter, No. 41, p. 37, 1996. [Cached copy]

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

%o (Magma) [Floor(24*(2^n-1)/n): n in [1..45]]; // _Vincenzo Librandi_, May 08 2011

%o (Python)

%o def A003176(n): return ((3<<n+3)-24)//n # _Chai Wah Wu_, Aug 24 2023

%Y Cf. A000799, A003138, A003177, A121056.

%K nonn

%O 1,1

%A _N. J. A. Sloane_