Numbers k such that 5*10^k - 81 is prime.

Terms

a(0) =2a(1) =3a(2) =4a(3) =13a(4) =15a(5) =22a(6) =24a(7) =28a(8) =111a(9) =148a(10) =248a(11) =294a(12) =476a(13) =1017a(14) =1875a(15) =2061a(16) =2068a(17) =2593a(18) =4462a(19) =6078a(20) =14457a(21) =14527a(22) =23679a(23) =33356a(24) =36484a(25) =50890a(26) =51608a(27) =113224