a(n) is the least k such that k*Mrs(n)*Mrs(n+1)*Mrs(n+2) + 1 is prime, where Mrs(n) is the n-th Mersenne prime.
A082747
a(n) is the least k such that k*Mrs(n)*Mrs(n+1)*Mrs(n+2) + 1 is prime, where Mrs(n) is the n-th Mersenne prime.
Terms
- a(0) =2a(1) =4a(2) =6a(3) =4a(4) =60a(5) =280a(6) =60a(7) =210a(8) =306a(9) =154a(10) =154a(11) =538a(12) =1272a(13) =640a(14) =4180a(15) =6384a(16) =12816a(17) =2020a(18) =10918a(19) =9694a(20) =45420a(21) =47506a(22) =11680a(23) =1408
External references
- oeis: A082747