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A057130 Product of first n primes of form 6k-1. 3
5, 55, 935, 21505, 623645, 25569445, 1201763915, 63693487495, 3757915762205, 266812019116555, 22145397586674065, 1970940385213991785, 199064978906613170285, 21299952743007609220495, 2406894659959859841915935, 315303200454741639290987485 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..16.

FORMULA

a(n) = a(n-1)*A007528(n) = (A057131(n)+1)/6.

EXAMPLE

a(3) = 5*11*17 = 935.

a(4) = 21505 = 5 * 11 * 17 * 23.

PROG

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

CROSSREFS

Cf. A000040, A002110, A002476, A006278, A007528, A074040, A078586, A121940.

Cf. A008543, A057131.

Sequence in context: A145662 A094418 A008543 * A141357 A093352 A293013

Adjacent sequences:  A057127 A057128 A057129 * A057131 A057132 A057133

KEYWORD

nonn,easy

AUTHOR

Henry Bottomley, Aug 11 2000

EXTENSIONS

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

More terms from Michel Marcus, Sep 08 2013

STATUS

approved

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Last modified August 6 12:33 EDT 2020. Contains 336246 sequences. (Running on oeis4.)