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A088270 Palindromic primes that yield a prime when sandwiched between two 3's. (Prefixing and suffixing a -three' on both sides yields another pal prime). 3
5, 7, 101, 151, 353, 727, 757, 929, 10301, 10601, 12721, 15551, 16061, 16661, 18181, 19391, 19891, 30403, 30703, 31013, 31513, 35353, 36263, 36563, 38083, 39293, 72227, 73237, 76367, 77377, 77477, 78487, 79397, 79997, 93139, 94649, 94849 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

EXAMPLE

757 is a member as 37573 is also a prime.

MATHEMATICA

s23Q[n_]:=Module[{idn=IntegerDigits[n]}, idn==Reverse[idn]&&PrimeQ[ FromDigits[Join[{3}, idn, {3}]]]]; Select[Prime[Range[10000]], s23Q] (* Harvey P. Dale, May 07 2011 *)

CROSSREFS

Cf. A088269, A088271, A088272.

Sequence in context: A176619 A230379 A292847 * A259496 A338525 A267586

Adjacent sequences: A088267 A088268 A088269 * A088271 A088272 A088273

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy, Sep 28 2003

EXTENSIONS

More terms from David Wasserman, Jul 28 2005

STATUS

approved

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Last modified January 30 19:10 EST 2023. Contains 359947 sequences. (Running on oeis4.)