Least k such that k*10^n-9, k*10^n-7, k*10^n-3 and k*10^n-1 are all prime.

Terms

a(0) =14a(1) =2a(2) =2a(3) =248a(4) =1856a(5) =7190a(6) =719a(7) =15308a(8) =13415a(9) =18434a(10) =13532a(11) =26975a(12) =6935a(13) =61763a(14) =17786a(15) =60140a(16) =6014a(17) =297974a(18) =103199a(19) =56321a(20) =80009a(21) =428186a(22) =303476a(23) =32558a(24) =1361063a(25) =444275a(26) =634451a(27) =116573a(28) =303593a(29) =293822