Numbers k such that k!4 + 2^2 is prime, where k!4 = k!!!! is the quadruple factorial number (A007662).
A291122
Numbers k such that k!4 + 2^2 is prime, where k!4 = k!!!! is the quadruple factorial number (A007662).
Terms
- a(0) =0a(1) =1a(2) =3a(3) =15a(4) =17a(5) =19a(6) =23a(7) =25a(8) =27a(9) =29a(10) =35a(11) =49a(12) =63a(13) =79a(14) =87a(15) =105a(16) =139a(17) =319a(18) =339a(19) =409a(20) =441a(21) =477a(22) =1023a(23) =1107a(24) =1517a(25) =1557a(26) =1625a(27) =4215a(28) =5297a(29) =6291
External references
- oeis: A291122