

A098027


Smallest prime p such that p+2 is a product of exactly n distinct primes.


0



3, 13, 103, 1153, 15013, 255253, 4849843, 111546433, 4360010653, 100280245063, 5245694198743, 152125131763603, 7149881192889433, 421842990380476663, 16294579238595022363, 1106494163767990292293, 74135108972455349583763
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OFFSET

1,1


COMMENTS

In most cases a(n) = pn!  2, where pn! is "factorial of odd primes": from 3 to nth odd prime.  Zak Seidov  Zak Seidov and Don Reble, Mar 10 2006


LINKS

Table of n, a(n) for n=1..17.


EXAMPLE

3+2=5 (1 prime), 13+2=15=3*5 (2 primes), 103+2=105=3*5*7 (3 primes), ...
1153 is the 4th entry in the sequence because it is followed by primes 1783, 1993, 2143, 2803, ... with the property 1153+2 = 3*5*7*11, 1783+2 = 3*5*7*17, 1993+2 = 3*5*7*19, 2143+2 = 3*5*11*13, 2803+2 = 3*5*11*17, ...


CROSSREFS

Cf. A067024 [From R. J. Mathar, Sep 02 2008]
Sequence in context: A068168 A215126 A228148 * A182104 A073587 A337869
Adjacent sequences: A098024 A098025 A098026 * A098028 A098029 A098030


KEYWORD

nonn


AUTHOR

Lekraj Beedassy, Sep 10 2004


EXTENSIONS

Extended by Ray Chandler, Sep 18 2004
More terms from Zak Seidov and Don Reble, Mar 10 2006
Corrected by Don Reble, Apr 03 2006


STATUS

approved



