A032728 n prefixed by '3' and followed by '9' is a prime.

4, 5, 7, 8, 10, 11, 16, 20, 22, 25, 29, 31, 32, 35, 38, 44, 46, 49, 52, 53, 55, 65, 70, 71, 73, 76, 77, 88, 91, 92, 98, 101, 103, 106, 107, 113, 115, 118, 121, 124, 125, 131, 137, 146, 148, 164, 169, 172, 176, 179, 184, 185, 200, 202, 205, 206, 208, 209, 211

Offset

0,1

Links

Harvey P. Dale, Table of n, a(n) for n = 0..1000

Mathematica

Select[Range[250], PrimeQ[FromDigits[Join[{3}, IntegerDigits[#], {9}]]]&] (* Harvey P. Dale, Aug 17 2021 *)

Crossrefs

Sequence in context: A288753 A202186 A247467 * A078577 A225387 A037259

Adjacent sequences: A032725 A032726 A032727 * A032729 A032730 A032731

Keyword

nonn,base

Author

Patrick De Geest, May 15 1998

Status

approved