cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A160405 Primes that are the concatenation of a 5-digit prime, a 7-digit prime, and a 5-digit prime.

Original entry on oeis.org

10007100000310037, 10007100000310163, 10007100000310247, 10007100000310271, 10007100000310289, 10007100000310321, 10007100000310433, 10007100000310463, 10007100000310477
Offset: 1

Views

Author

Walter Nissen, May 13 2009

Keywords

Comments

Haiku-haiku-haiku primes. I would like to call these "Haiku primes" but it seems that name has been used by Geoffrey Caveney for a different concept. Another possible name would be haiku-formed primes, but maybe that should be reserved for primes which are formed from any number of primes of width 5 or 7. Note that if you associate the hyphens with the central word, Haiku-haiku-haiku is itself of the 5-7-5 form (in characters).

Examples

			10007, 1000003, 10037, and 10007100000310037 are all prime, so 10007100000310037 is in the sequence.
		

Crossrefs

Cf. A000040 (primes), A006879 (number of primes with n digits).

Programs

  • Magma
    [ a: p in PrimesInInterval(10000,10007), q in PrimesInInterval(1000000,1000003), r in PrimesInInterval(10000,12000) | IsPrime(a) where a is Seqint(Intseq(r) cat Intseq(q) cat Intseq(p)) ]; // Klaus Brockhaus, May 20 2009

Extensions

Edited by Klaus Brockhaus, May 20 2009