

A018239


Primorial primes: form product of first k primes and add 1, then reject unless prime.


22



2, 3, 7, 31, 211, 2311, 200560490131, 1719620105458406433483340568317543019584575635895742560438771105058321655238562613083979651479555788009994557822024565226932906295208262756822275663694111
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OFFSET

1,1


COMMENTS

Prime numbers that are the sum of two primorial numbers.  JuriStepan Gerasimov, Nov 08 2010


REFERENCES

F. Iacobescu, Smarandache Partition Type and Other Sequences, Bull. Pure Appl. Sciences, Vol. 16E, No. 2 (1997), pp. 237240.


LINKS

Table of n, a(n) for n=1..8.
M. Fleuren, Factors and primes of Smarandache sequences.
M. Fleuren, Smarandache Prime Product Sequence.
R. Mestrovic, Euclid's theorem on the infinitude of primes: a historical survey of its proofs (300 BC2012) and another new proof, arXiv preprint arXiv:1202.3670, 2012  From N. J. A. Sloane, Jun 13 2012
F. Smarandache, Sequences of Numbers Involved in Unsolved Problems.
R. Ondrejka, PrimorialPlusOne Primes


MATHEMATICA

Select[FoldList[Times, 1, Prime[Range[200]]] + 1, PrimeQ]. (* Loreno Heer (helohe(AT)bluewin.ch), Jun 29 2004 *)


PROG

(PARI) P=1; print1(2); forprime(p=2, 1e6, if(isprime(1+P*=p), print1(", "P+1))) \\ Charles R Greathouse IV, Apr 28 2015


CROSSREFS

Primes in A006862 (primorials plus 1).
A005234 and A014545 (which are the main entries for this sequence) give more terms.
Cf. A002110.
Sequence in context: A241196 A073918 A096350 * A066279 A161471 A057677
Adjacent sequences: A018236 A018237 A018238 * A018240 A018241 A018242


KEYWORD

nonn,nice


AUTHOR

Murray R. Bremner


EXTENSIONS

Edited by N. J. A. Sloane at the suggestion of Vladeta Jovovic, Jun 18 2007


STATUS

approved



