a(n) is the smallest b >= 2 such that 1 + Sum_{k=0..n} b^(2^k) is prime, or 1 if no such b exists.
A352736
a(n) is the smallest b >= 2 such that 1 + Sum_{k=0..n} b^(2^k) is prime, or 1 if no such b exists.
Terms
- a(0) =2a(1) =2a(2) =2a(3) =1a(4) =6a(5) =3a(6) =448a(7) =107a(8) =104a(9) =1a(10) =4556a(11) =1a(12) =24124a(13) =121209a(14) =368a(15) =177817a(16) =48330a(17) =1
External references
- oeis: A352736