A088283 Palindromic primes in which a single digit is sandwiched between strings of 7's.

727, 757, 787, 797, 77377, 77477, 77977, 7772777, 7774777, 7778777, 777767777, 77777677777, 7777774777777, 777777727777777, 777777757777777, 77777777677777777, 77777777977777777, 777777777727777777777

Offset

1,1

Links

Harvey P. Dale, Table of n, a(n) for n = 1..37

Mathematica

Select[Flatten[Table[FromDigits[Flatten[Join[{PadRight[{}, n, 7], i, PadRight[ {}, n, 7]}]]], {n, 10}, {i, 0, 9}]], PrimeQ] (* Harvey P. Dale, Jun 15 2015 *)

Crossrefs

Cf. A088281, A088282, A088284.

Sequence in context: A090268 A090267 A068688 * A123096 A108846 A052234

Adjacent sequences: A088280 A088281 A088282 * A088284 A088285 A088286

Keyword

base,nonn

Author

Amarnath Murthy, Sep 29 2003

Extensions

More terms from David Wasserman, Aug 03 2005

Status

approved