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%I #2 Mar 30 2012 17:25:42
%S 1,4444,666666,88888888,999999999,10101010101010101010,
%T 121212121212121212121212,1414141414141414141414141414,
%U 151515151515151515151515151515,16161616161616161616161616161616
%N Nonprime numbers n concatenated n times.
%e 4 is a nonprime and it is concatenated four times to give 4444.
%K nonn,base
%O 1,2
%A _Parthasarathy Nambi_, Jan 31 2005