A173510 - OEIS

%I #11 Mar 12 2014 16:37:13

%S 2,1,3,3,5,6,8,10,13,17,22,28,36,46,59,76,97,125,160,205,263,337,432,

%T 553,709,908,1163,1490,1908,2444,3130,4009,5135,6577,8424,10789,13819,

%U 17699,22669,29034,37186,47627,61000,78127,100064,128159,164144,210231,269260,344861,441691

%N a(n) = a(n-1) + a(n-2) - floor( a(n-1)/2 ).

%C The limiting ratio a(n+1)/a(n)is:1.2807764064

%t l[0] = 2; l[1] = 1;

%t l[n_] := l[n] = l[n - 1] + l[n - 2] - Floor[l[n - 1]/2]

%t Table[l[n], {n, 0, 30}]

%t RecurrenceTable[{a[0]==2,a[1]==1,a[n]==a[n-1]+a[n-2]-Floor[a[n-1]/2]},a,{n,50}] (* _Harvey P. Dale_, Sep 03 2013 *)

%o (Maxima) A173510[n] := block(

%o         if equal(n,0) then return(2) ,

%o         if equal(n,1) then return(1)

%o         else

%o         return(ev(A173510[n-1]+A173510[n-2]-floor(A173510[n-1]/2)))

%o )$ /* R. J. Mathar, Mar 11 2012 */

%Y Cf. A000032.

%K nonn

%O 0,1

%A _Roger L. Bagula_, Nov 23 2010