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a(1) = 1; a(n) is the smallest multiple of a(n-1) not divisible by 10 which is greater than the digit reversal of a(n-1). In case R(a(n-1)) < a(n-1) then a(n) = 2*a(n-1).
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%I #4 Dec 05 2013 19:55:46

%S 1,2,4,8,16,64,128,896,1792,3584,7168,14336,86016,172032,344064,

%T 688128,1376256,8257536,16515072,33030144,66060288,132120576,

%U 792723456,1585446912,3170893824,6341787648,12683575296,76101451776,152202903552

%N a(1) = 1; a(n) is the smallest multiple of a(n-1) not divisible by 10 which is greater than the digit reversal of a(n-1). In case R(a(n-1)) < a(n-1) then a(n) = 2*a(n-1).

%e a(4) = 16 hence a(5) =64 = 4*16 >61. But 64 is > 46 hence a(6) = 2*64 = 128.

%K base,nonn

%O 1,2

%A _Amarnath Murthy_, Oct 07 2002

%E More terms from _David Wasserman_, Mar 25 2005