A145743 a(n) is the smallest composite number m such that all n numbers m+4*k^2 for k=1,2,...,n are prime.

9, 15, 25, 25, 247, 583, 5377, 143473, 143473, 143473, 2821813, 62087033647, 91450844347

Offset: 1

Author

Farideh Firoozbakht, Oct 17 2008

Keywords

• more
• nonn

Comments

There is no further term up to 5*10^8.

Crossrefs

Cf. A145741, A145742.

Extensions

a(12)-a(13) from Donovan Johnson, Nov 17 2008