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%I #14 Jan 03 2024 23:43:16
%S 111,1221,13331,144441,1555551,16666661,177777771,1888888881,
%T 19999999991,1101010101010101010101,111111111111111111111111,
%U 11212121212121212121212121,1131313131313131313131313131,114141414141414141414141414141,11515151515151515151515151515151
%N 1 concatenated with n n's concatenated with 1.
%e a(7) = 177777771.
%t Table[FromDigits[Join[{1},Flatten[IntegerDigits/@Table[n,{n}]],{1}]],{n,15}] (* _Harvey P. Dale_, Apr 19 2013 *)
%Y Cf. A000461 (concatenate n n times).
%K easy,nonn,base
%O 1,1
%A _Ctibor O. Zizka_, Apr 19 2008
%E More terms from _Harvey P. Dale_, Apr 19 2013