A211979 Numbers n formed by p 1's followed by p - 1 0's, where p is prime(n).

110, 11100, 111110000, 1111111000000, 111111111110000000000, 1111111111111000000000000, 111111111111111110000000000000000, 1111111111111111111000000000000000000, 111111111111111111111110000000000000000000000

Offset

1,1

Links

Table of n, a(n) for n=1..9.

Example

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

Mathematica

(* Technically this is in base 10 *) Table[10^(Prime[n] - 1)((10^Prime[n] - 1)/9), {n, 20}] (* Alonso del Arte, Dec 12 2012 *)
FromDigits[Join[PadRight[{}, #, 1], PadRight[{}, #-1, 0]]]&/@ Prime[ Range[ 10]] (* Harvey P. Dale, Aug 30 2015 *)

Crossrefs

Binary representation of A060286.

a(n) has A076274(n) digits.

Cf. A007088, A076274, A109241, A135650.

Sequence in context: A109241 A090490 A267688 * A135650 A193240 A267775

Adjacent sequences: A211976 A211977 A211978 * A211980 A211981 A211982

Keyword

nonn,base

Author

Omar E. Pol, Dec 12 2012

Status

approved