

A057131


One less than six times product of first n primes of form 6k1.


1



29, 329, 5609, 129029, 3741869, 153416669, 7210583489, 382160924969, 22547494573229, 1600872114699329, 132872385520044389, 11825642311283950709, 1194389873439679021709, 127799716458045655322969, 14441367959759159051495609, 1891819202728449835745924909
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OFFSET

1,1


COMMENTS

a(n)=5 mod 6, so a(n) has at least one prime factor of form 6k1 and this is not one of those included in the calculation of a(n); for example 5609 has 71 as a prime factor. Therefore there are an infinite number of prime numbers of form 6k1 (and also of form 3k1).


LINKS



FORMULA



EXAMPLE

a(3) = 6*(5*11*17)1 = 5609.


PROG

(PARI) lista(nn) = {pp = 6; for (n = 1, nn, p = prime(n); if (Mod(p, 6) == 1, pp *= p; print1(pp1, ", ")); ); } \\ Michel Marcus, Sep 08 2013


CROSSREFS



KEYWORD

nonn,easy


AUTHOR



EXTENSIONS

More terms from Larry Reeves (larryr(AT)acm.org), Oct 06 2000


STATUS

approved



