A076682 Numbers k such that 6*k! + 1 is prime.

0, 1, 2, 3, 7, 8, 9, 12, 13, 18, 24, 38, 48, 60, 113, 196, 210, 391, 681, 739, 778, 1653, 1778, 1796, 1820, 2391, 2505, 4595, 8937

Offset: 1

Author

Phillip L. Poplin (plpoplin(AT)bellsouth.net), Oct 25 2002

Keywords

• nonn
• more

Comments

a(29) > 5800. - Jinyuan Wang, Feb 05 2020

a(30) > 12000. - Michael S. Branicky, Jul 04 2024

Examples

			k = 3 is here because 6*3! + 1 = 37 is prime.
		

Crossrefs

Cf. A002981, A051915, A076679, A076680, A076681, A076683, A178488, A180626, A126896.

Programs

PARI

is(k) = ispseudoprime(6*k!+1); \\ Jinyuan Wang, Feb 05 2020

Extensions

a(26) inserted by and a(29) from Michael S. Branicky, Jul 03 2024