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A160405 Primes that are the concatenation of a 5-digit prime, a 7-digit prime, and a 5-digit prime. 0
10007100000310037, 10007100000310163, 10007100000310247, 10007100000310271, 10007100000310289, 10007100000310321, 10007100000310433, 10007100000310463, 10007100000310477 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

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).

LINKS

Table of n, a(n) for n=1..9.

Wikipedia, Haiku

EXAMPLE

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

PROG

(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

CROSSREFS

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

Sequence in context: A320865 A274810 A329948 * A162032 A141621 A095432

Adjacent sequences:  A160402 A160403 A160404 * A160406 A160407 A160408

KEYWORD

base,fini,nonn

AUTHOR

Walter Nissen, May 13 2009

EXTENSIONS

Edited by Klaus Brockhaus, May 20 2009

STATUS

approved

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Last modified August 6 09:02 EDT 2020. Contains 336228 sequences. (Running on oeis4.)