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Numbers n formed by p 1's followed by p - 1 0's, where p is prime(n).
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%I #20 Apr 06 2020 19:01:42

%S 110,11100,111110000,1111111000000,111111111110000000000,

%T 1111111111111000000000000,111111111111111110000000000000000,

%U 1111111111111111111000000000000000000,111111111111111111111110000000000000000000000

%N Numbers n formed by p 1's followed by p - 1 0's, where p is prime(n).

%e For n = 3, the third prime is 5, so a(3) = 111110000 (five 1's followed by four 0's).

%t (* Technically this is in base 10 *) Table[10^(Prime[n] - 1)((10^Prime[n] - 1)/9), {n, 20}] (* _Alonso del Arte_, Dec 12 2012 *)

%t FromDigits[Join[PadRight[{},#,1],PadRight[{},#-1,0]]]&/@ Prime[ Range[ 10]] (* _Harvey P. Dale_, Aug 30 2015 *)

%Y Binary representation of A060286.

%Y a(n) has A076274(n) digits.

%Y Cf. A007088, A076274, A109241, A135650.

%K nonn,base

%O 1,1

%A _Omar E. Pol_, Dec 12 2012