A147788 a(n) = floor(2*(3/2)^n).

2, 3, 4, 6, 10, 15, 22, 34, 51, 76, 115, 172, 259, 389, 583, 875, 1313, 1970, 2955, 4433, 6650, 9975, 14963, 22445, 33668, 50502, 75753, 113630, 170445, 255668, 383502, 575253, 862879, 1294319, 1941479, 2912219, 4368328, 6552493, 9828739, 14743109

Offset

0,1

Comments

Different from the sequence defined by the recursion a(1) = 3, a(n) = floor(a(n-1)*3/2) for n > 1, which gives a(2) = 4, a(3) = 6, a(4) = 9, a(5) = 13, ... (cf. A061418). - Klaus Brockhaus, Nov 16 2008

Links

Table of n, a(n) for n=0..39.

Example

a(4) = floor(2*(3/2)^4) = floor(81/8) = floor(10+1/8) = 10. - Klaus Brockhaus, Nov 16 2008

Mathematica

lst={}; s=2; Do[s=s*1.5; AppendTo[lst, Floor[s]], {n, 1, 5!}]; lst
Floor[2 (3/2)^Range[0, 40]] (* Harvey P. Dale, Aug 28 2019 *)

Prog

(Magma) [ Floor(2*(3/2^n):n in [1..39] ]; // Klaus Brockhaus, Nov 16 2008
(Python)
def A147788(n): return 3**n>>n-1 if n else 2 # Chai Wah Wu, Sep 21 2022

Crossrefs

Cf. A061418, A147789, A147790.

Sequence in context: A086990 A090412 A073028 * A104977 A206742 A221992

Adjacent sequences: A147785 A147786 A147787 * A147789 A147790 A147791

Keyword

nonn

Author

Vladimir Joseph Stephan Orlovsky, Nov 13 2008

Extensions

Definition clarified by R. J. Mathar, Nov 14 2008

Edited by N. J. A. Sloane, Nov 18 2008

Status

approved