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a(1) = 1, a(2) = 3, a(n+1) = least number of the form k*(a(n-1)) - a(n), not included earlier.
1

%I #5 Dec 05 2013 19:57:14

%S 1,3,2,4,6,10,8,12,20,16,24,40,32,48,80,64,96,160,128,192,320,256,384,

%T 640,512,768,1280,1024,1536,2560,2048,3072,5120,4096,6144,10240,8192,

%U 12288,20480,16384,24576,40960,32768,49152,81920,65536,98304,163840

%N a(1) = 1, a(2) = 3, a(n+1) = least number of the form k*(a(n-1)) - a(n), not included earlier.

%C a(3n+4) = 2*a(3n+1)= 2^(n+2). a(3n+5) = 2*a(3n+2). = 3*2^(n+1). a(3n+6) = 2*a(3n+3). =5*2^(n). From a(4) on the terms match A114743.

%Y Cf. A114743, A114744.

%K nonn

%O 1,2

%A _Amarnath Murthy_, Nov 15 2005

%E More terms from _R. J. Mathar_, Aug 31 2007