A275275 n! - p, where p is the second greatest prime < n!.

4, 5, 3, 5, 11, 11, 17, 37, 17, 17, 17, 13, 61, 17, 59, 71, 61, 43, 113, 71, 41, 101, 191, 103, 191, 179, 71, 127, 37, 79, 113, 163, 47, 373, 293, 157, 149, 79, 167, 211, 151, 89, 131, 113, 73, 107, 179, 227, 173, 113, 257, 239, 151, 227, 163, 509, 293, 347

Offset

1,1

Comments

Is every term except 4 a prime?

Links

Clark Kimberling, Table of n, a(n) for n = 1..300

Example

For n = 4, we have n! = 24, so that p = 19, and a(4) = 5.

Mathematica

Table[n! - NextPrime[n!, -2], {n, 1, 150}]

Crossrefs

Cf. A275272, A000040.

Sequence in context: A021692 A222627 A107793 * A376180 A196402 A268741

Adjacent sequences: A275272 A275273 A275274 * A275276 A275277 A275278

Keyword

nonn,easy

Author

Clark Kimberling, Jul 23 2016

Status

approved