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 A061419 a(n) = ceiling(a(n-1)*3/2) with a(1) = 1. 22

%I

%S 1,2,3,5,8,12,18,27,41,62,93,140,210,315,473,710,1065,1598,2397,3596,

%T 5394,8091,12137,18206,27309,40964,61446,92169,138254,207381,311072,

%U 466608,699912,1049868,1574802,2362203,3543305,5314958,7972437,11958656

%N a(n) = ceiling(a(n-1)*3/2) with a(1) = 1.

%C It appears that this sequence is the (L)-sieve transform of {3,6,9,12,...,3n,...} = A008585. (See A152009 for the definition of the (L)-sieve transform.) - _John W. Layman_, Jan 06 2009

%D Z. Deniz, Topology of acyclic complexes of tournaments and coloring, Applicable Algebra in Engineering, Communication, March 2015, Volume 26, Issue 1, pp 213-226.

%H Harry J. Smith, <a href="/A061419/b061419.txt">Table of n, a(n) for n = 1..500</a>

%H A. Dubickas, <a href="https://doi.org/10.1017/S0017089508004655">On integer sequences generated by linear maps</a>, Glasg. Math. J. 51, No. 2, 243-252 (2009).

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PowerCeilings.html">Power Ceilings</a>

%F a(n) = A061418(n) - 1 = floor(K*(3/2)^n) where K = 1.08151366859...

%F The constant K is 2/3*K(3) (see A083286). - _Ralf Stephan_, May 29, 2003

%F a(1) = 1, a(n) = A070885(n)/3. - _Benoit Cloitre_, Aug 18 2002

%F a(n) = ceiling((a(n-1) + a(n-2))*9/10) - _Franklin T. Adams-Watters_, May 01 2006

%e a(6) = ceiling(8*3/2) = 12.

%p a:=proc(n) option remember: if n=1 then 1 else ceil(procname(n-1)*3/2) fi; end; seq(a(n),n=1..40); # _Muniru A Asiru_, Jun 07 2018

%t a=1;a=Table[a=Ceiling[a*3/2],{n,0,4!}] (* _Vladimir Joseph Stephan Orlovsky_, Apr 13 2010 *)

%o (MAGMA) [ n eq 1 select 1 else Ceiling(Self(n-1)*3/2): n in [1..40] ]; // _Klaus Brockhaus_, Nov 14 2008

%o (PARI) { a=2/3; for (n=1, 500, write("b061419.txt", n, " ", a=ceil(a*3/2)) ) } \\ _Harry J. Smith_, Jul 22 2009

%Y Cf. A002379, A034082, A061418, A061420, A003312.

%Y First differences are in A073941.

%K nonn

%O 1,2

%A _Henry Bottomley_, May 02 2001

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Last modified August 22 08:09 EDT 2019. Contains 326172 sequences. (Running on oeis4.)