A066576 Composite Euclid numbers: numbers of the form p# + 1, where p# denotes the primorial of the prime p.

30031, 510511, 9699691, 223092871, 6469693231, 7420738134811, 304250263527211, 13082761331670031, 614889782588491411, 32589158477190044731, 1922760350154212639071, 117288381359406970983271

Offset

1,1

Comments

30031 appears in Wells's "Curious and Interesting Numbers" as the smallest composite number of the form p# + 1.

References

David Wells, "The Penguin Dictionary of Curious and Interesting Numbers," Revised Edition, Penguin Books, London, England, 1997, page 166.

Links

Amiram Eldar, Table of n, a(n) for n = 1..341

Mathematica

Do[c = Product[ Prime[i], {i, 1, n}] + 1; If[ !PrimeQ[c], Print[c]], {n, 1, 20} ]

Prog

(Magma) [a: n in [2..19]| not IsPrime(a) where a is 1+&*[NthPrime(k):k in [1..n]]]; // Marius A. Burtea, Feb 18 2020

Crossrefs

Cf. A014545, A006862.

Sequence in context: A046324 A138206 A031853 * A104877 A237031 A027665

Adjacent sequences: A066573 A066574 A066575 * A066577 A066578 A066579

Keyword

nonn

Author

Joseph L. Pe, Jan 07 2002

Extensions

Edited by Robert G. Wilson v, Jan 09 2002

Status

approved