A032730 n prefixed by '5' and followed by '9' is a prime.

0, 6, 9, 11, 17, 18, 20, 27, 30, 39, 41, 44, 47, 51, 56, 63, 65, 66, 68, 74, 77, 83, 84, 86, 87, 93, 105, 110, 116, 119, 122, 123, 132, 134, 141, 143, 144, 147, 153, 159, 165, 167, 171, 174, 176, 182, 183, 185, 186, 189, 192, 194, 200, 206, 218, 224, 225

Offset

0,2

Links

Table of n, a(n) for n=0..56.

Mathematica

Select[Range[0, 250], PrimeQ[FromDigits[Join[{5}, IntegerDigits[#], {9}]]]&] (* Harvey P. Dale, May 09 2011 *)

Crossrefs

Sequence in context: A202137 A302580 A031256 * A275274 A131834 A084418

Adjacent sequences: A032727 A032728 A032729 * A032731 A032732 A032733

Keyword

nonn,base

Author

Patrick De Geest, May 15 1998

Status

approved