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%I #20 Nov 02 2024 15:34:49
%S 2,3,4,6,10,15,22,34,51,76,115,172,259,389,583,875,1313,1970,2955,
%T 4433,6650,9975,14963,22445,33668,50502,75753,113630,170445,255668,
%U 383502,575253,862879,1294319,1941479,2912219,4368328,6552493,9828739,14743109
%N a(n) = floor(2*(3/2)^n).
%C 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
%e a(4) = floor(2*(3/2)^4) = floor(81/8) = floor(10+1/8) = 10. - _Klaus Brockhaus_, Nov 16 2008
%t lst={};s=2;Do[s=s*1.5;AppendTo[lst,Floor[s]],{n,1,5!}];lst
%t Floor[2 (3/2)^Range[0,40]] (* _Harvey P. Dale_, Aug 28 2019 *)
%o (Magma) [ Floor(2*(3/2)^n):n in [1..39] ]; // _Klaus Brockhaus_, Nov 16 2008
%o (Python)
%o def A147788(n): return 3**n>>n-1 if n else 2 # _Chai Wah Wu_, Sep 21 2022
%Y Cf. A061418, A147789, A147790.
%K nonn
%O 0,1
%A _Vladimir Joseph Stephan Orlovsky_, Nov 13 2008
%E Definition clarified by _R. J. Mathar_, Nov 14 2008
%E Edited by _N. J. A. Sloane_, Nov 18 2008