A088284 Palindromic primes in which a single digit is sandwiched between nonempty strings of 9's.

919, 929, 99999199999, 99999999299999999, 9999999992999999999, 999999999999919999999999999, 99999999999999499999999999999, 999999999999999999999949999999999999999999999, 99999999999999999999999999899999999999999999999999999

Offset

1,1

Links

Alois P. Heinz, Table of n, a(n) for n = 1..20

Hans Havermann, Near-rep-nine palindromic primes

Mathematica

Select[Flatten[Table[FromDigits[Join[PadRight[{}, n, 9], {d}, PadRight[{}, n, 9]]], {n, 30}, {d, Range[8]}]], PrimeQ] (* Harvey P. Dale, Mar 17 2023 *)

Crossrefs

Subsequence of A002385.

Cf. A088281, A088282, A088283.

Sequence in context: A082518 A128375 A068689 * A020399 A084843 A059668

Adjacent sequences: A088281 A088282 A088283 * A088285 A088286 A088287

Keyword

base,nonn

Author

Amarnath Murthy, Sep 29 2003

Extensions

More terms from David Wasserman, Aug 03 2005

Name clarified by Christian Stump, Mar 31 2015

Status

approved