a(n) = least k such that 2*i*k - 1 is prime for 1 <= i <= n.

A124492

a(n) = least k such that 2*i*k - 1 is prime for 1 <= i <= n.

Terms

    a(0) =2a(1) =2a(2) =2a(3) =3a(4) =3a(5) =77385a(6) =1447110a(7) =1447110a(8) =203937090a(9) =107290072890

External references