A081712 -id:A081712 - cp's OEIS frontend

A081710 n! + n# + 1 is prime, where n# is the primorial function.

1, 2, 3, 4, 5, 6, 8, 17, 18, 24, 95, 96, 142, 1022, 1120, 1580, 6942, 19255, 19401

Offset: 1

Mike Oakes, Apr 04 2003

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

			a(2)=2 because 2!+2#+1=5 is prime

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

Cf. A081711, A081712, A081713.

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

A081711 Numbers k such that k! + k# - 1 is prime, where k# is the primorial function A034386(k).

Original entry on oeis.org

2, 3, 4, 5, 8, 17, 23, 26, 35, 47, 82, 100, 147, 183, 271, 492, 708, 1116, 1538, 2491, 4207, 4468, 8147

Offset: 1

Mike Oakes, Apr 04 2003

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

			a(1)=2 because 2!+2#-1=3 is prime

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

Cf. A034386, A081710, A081712, A081713.

Offset and ordering corrected by Sean A. Irvine, Sep 18 2023

a(23) from Michael S. Branicky, May 06 2025

A081713 n! - n# - 1 is prime, where n# is the primorial function.

Original entry on oeis.org

4, 5, 20, 92, 106, 266, 308, 343, 583, 597, 903, 1021, 1239, 1314, 2458, 6160, 9627, 10649

Offset: 1

Mike Oakes, Apr 04 2003

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

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

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.

Cf. A081710, A081711, A081712.

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

cp's OEIS Frontend

A081710 n! + n# + 1 is prime, where n# is the primorial function.

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A081711 Numbers k such that k! + k# - 1 is prime, where k# is the primorial function A034386(k).

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A081713 n! - n# - 1 is prime, where n# is the primorial function.

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