A068680 Primes formed by the concatenation n, n+2, n.

131, 353, 797, 171917, 232523, 272927, 293129, 313331, 333533, 373937, 495149, 515351, 575957, 596159, 616361, 636563, 676967, 737573, 777977, 798179, 838583, 878987, 899189, 103105103, 109111109, 111113111, 129131129, 133135133

Offset

1,1

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Example

109111109 is a term as it is the concatenation of 109, 111 and 109.

Mathematica

Select[Table[FromDigits[Join[IntegerDigits[n], IntegerDigits[n+2], IntegerDigits[ n]]], {n, 200}], PrimeQ] (* Harvey P. Dale, Jul 13 2018 *)

Crossrefs

Sequence in context: A242846 A395311 A142129 * A276255 A142555 A118507

Adjacent sequences: A068677 A068678 A068679 * A068681 A068682 A068683

Keyword

base,easy,nonn

Author

Amarnath Murthy, Mar 02 2002

Status

approved