A174858 Primes p such that p + 2, p + 6, and the concatenation p (p+2) (p+6) is prime.

5, 11, 17, 41, 11171, 16061, 16187, 20897, 29021, 34841, 36011, 39227, 41177, 51341, 55331, 56891, 58907, 63311, 64151, 69191, 77261, 82757, 113021, 122027, 123731, 135461, 151337, 167621, 173291, 174761, 187631, 191447, 195731, 203207, 203381, 225341, 227531

Offset

1,1

Links

Harvey P. Dale, Table of n, a(n) for n = 1..1000

Example

(5,7,11) is the first prime triple and their concatenation 5711 is prime, so 5 is a term of sequence.
(11,13,17) is the second prime triple and their concatenation 111317 is prime, so 11 is a term of sequence.

Maple

q:= p-> andmap(isprime, [p+2, p+6, parse(cat(p, p+2, p+6))]):
select(q, [ithprime(i)$i=1..20225])[];  # Alois P. Heinz, Jan 29 2026

Mathematica

Transpose[Select[Partition[Prime[Range[20000]], 3, 1], Differences[#]=={2, 4} && PrimeQ[ FromDigits[Flatten[IntegerDigits/@#]]]&]][[1]] (* Harvey P. Dale, Apr 10 2013 *)

Crossrefs

Subsequence of A022004.

Sequence in context: A162001 A171713 A375313 * A246704 A095183 A018730

Adjacent sequences: A174855 A174856 A174857 * A174859 A174860 A174861

Keyword

base,nonn

Author

Ulrich Krug (leuchtfeuer37(AT)gmx.de), Mar 31 2010

Status

approved