A103818 Primes p such that p and p+2 are twin primes and also the strings 987654321p and 987654321p+2 are twin primes.

569, 1019, 2267, 2801, 3917, 5879, 8231, 8999, 18917, 19139, 25301, 26111, 27281, 30089, 40127, 42071, 43319, 53279, 55337, 57527, 75539, 80747, 84317, 103991, 106961, 117701, 149519, 154157, 154871, 156491, 159347, 160709, 201827, 208589

Offset

1,1

Links

Table of n, a(n) for n=1..34.

Example

569 and 571 are twin primes, also 987654321569 and 987654321571 are twin primes.

Mathematica

fQ[n_] := Block[{p = IntegerDigits[n], q = IntegerDigits[n + 2], r = {9, 8, 7, 6, 5, 4, 3, 2, 1}}, If[ PrimeQ[n + 2] && PrimeQ[ FromDigits[ Join[r, p]]] && PrimeQ[ FromDigits[ Join[r, q]]], True, False]]; Select[ Prime[ Range[ 19400]], fQ[ # ] &] (* Robert G. Wilson v, Mar 30 2005 *)

Crossrefs

Sequence in context: A192822 A356443 A142818 * A240715 A263708 A219992

Adjacent sequences: A103815 A103816 A103817 * A103819 A103820 A103821

Keyword

nonn,base

Author

Zak Seidov, Mar 30 2005

Extensions

More terms from Robert G. Wilson v, Mar 30 2005

Status

approved