Voozh

A060882

a(n) = n-th primorial (A002110) minus next prime.

-1, -1, 1, 23, 199, 2297, 30013, 510491, 9699667, 223092841, 6469693199, 200560490093, 7420738134769, 304250263527167, 13082761331669983, 614889782588491357, 32589158477190044671, 1922760350154212639009

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OFFSET

0,4

COMMENTS

It is well-known and easy to prove (see Honsbeger) that a(n) > 0 for n > 1. - N. J. A. Sloane, Jul 05 2009

Terms are pairwise coprime with very high probability. I didn't find terms which are pairwise noncoprime, although it may be a case of the "strong law of small numbers." - Daniel Forgues, Apr 23 2012

REFERENCES

R. Honsberger, Mathematical Diamonds, MAA, 2003, see p. 79. [Added by N. J. A. Sloane, Jul 05 2009]

LINKS

Harry J. Smith, Table of n, a(n) for n = 0..100

Hisanori Mishima, P1 * Pn + NextPrime (n = 1 to 100)

Hisanori Mishima, P1 * Pn - NextPrime (n = 1 to 100)

Hisanori Mishima, P1 * Pn + 1 (n = 1 to 100)

Hisanori Mishima, P1 * Pn - 1 (n = 1 to 100)

Hisanori Mishima, WIFC (World Integer Factorization Center)

MAPLE

pp:=n->mul(ithprime(i), i=1..n);

[seq(pp(n)-ithprime(n+1), n=1..20)];