A240161 Numbers n such that (k!-n)/k is prime for some k.

4, 5, 7, 8, 12, 13, 15, 16, 25, 31, 33, 34, 35, 39, 42, 55, 65, 66, 77, 78, 85, 95, 102, 105, 110, 114, 121, 130, 133, 136, 138, 152, 156, 167, 169, 170, 186, 187, 203, 204, 221, 222, 232, 246, 248, 253, 255, 259, 279, 282, 290, 294, 296, 301, 318, 322, 325, 328, 329, 333, 354, 366

Offset: 1

Author

Derek Orr, Aug 01 2014

Keywords

• nonn

Comments

Numbers n such that A240160(n) is not null. - Michel Marcus, Aug 05 2014

Links

• Jens Kruse Andersen, Table of n, a(n) for n = 1..300

Crossrefs

Cf. A240160, A240163.

Programs

PARI

a(n)=for(k=1,n,s=(k!-n)/k;if(floor(s)==s,if(ispseudoprime(s),return(k))))
n=1;while(n<500,if(a(n),print1(n,", "));n++)