Least j such that 6*p(j)*M(n)-1 is prime with p(j)=j-th prime and M(n) = Mersenne prime.

Terms

a(0) =2a(1) =1a(2) =2a(3) =1a(4) =4a(5) =3a(6) =12a(7) =31a(8) =2a(9) =14a(10) =19a(11) =15a(12) =17a(13) =467a(14) =37a(15) =111a(16) =1382a(17) =4830a(18) =276a(19) =1962a(20) =360a(21) =1749a(22) =2857a(23) =17253a(24) =9414a(25) =11974a(26) =30167a(27) =18822a(28) =21387a(29) =24721