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a(1) = 12, a(n+1) = lcm{a(n), Digit Reversal(a(n))}.
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%I #12 Sep 03 2017 03:31:49

%S 12,84,336,70896,1649679024,2314922791895828688,

%T 36399640682124013852413819710318544,

%U 77273493636380731521261660069550949170528534841641864516576194470832

%N a(1) = 12, a(n+1) = lcm{a(n), Digit Reversal(a(n))}.

%C Next term has 135 digits.

%e a(3) = lcm(84,48) = 336.

%p rev:=proc(n) local nn, nnn: nn:=convert(n,base,10): add(nn[nops(nn)+1-j]*10^(j-1),j=1..nops(nn)) end: a[1]:=12: for n from 1 to 8 do a[n+1]:=lcm(a[n],rev(a[n])) od: seq(a[n],n=1..8); # _Emeric Deutsch_, Aug 11 2005

%t NestList[LCM[#,FromDigits[Reverse[IntegerDigits[#]]]]&,12,8] (* _Harvey P. Dale_, Jan 09 2011 *)

%K base,nonn

%O 1,1

%A _Amarnath Murthy_, Aug 04 2005

%E More terms from _Emeric Deutsch_, Aug 11 2005