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A081713 n! - n# - 1 is prime, where n# is the primorial function. 3
4, 5, 20, 92, 106, 266, 308, 343, 583, 597, 903, 1021, 1239, 1314, 2458, 6160, 9627, 10649 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Some of the larger entries may only correspond to probable primes.

LINKS

Table of n, a(n) for n=1..18.

Mike Oakes, Primo-factorials.

Mike Oakes, Primo-factorials, message 12028 in primenumbers Yahoo group, Apr 3, 2003. [Cached copy]

Joe McLean, Interesting Sources of Probable Primes.

EXAMPLE

a(1)=4 because 4!-4#-1=17 is prime

CROSSREFS

Cf. A081710, A081711, A081712.

Sequence in context: A119283 A151499 A057781 * A344950 A344151 A120697

Adjacent sequences:  A081710 A081711 A081712 * A081714 A081715 A081716

KEYWORD

nonn,more,hard

AUTHOR

Mike Oakes, Apr 04 2003

EXTENSIONS

More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), Jan 03 2008

STATUS

approved

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Last modified December 1 11:30 EST 2021. Contains 349429 sequences. (Running on oeis4.)