Smaller term of closest safe prime pairs.

Terms

a(0) =11a(1) =47a(2) =167a(3) =347a(4) =467a(5) =1307a(6) =2027a(7) =2447a(8) =4127a(9) =4787a(10) =5087a(11) =5387a(12) =5927a(13) =12527a(14) =12647a(15) =15287a(16) =18947a(17) =28307a(18) =39107a(19) =39827a(20) =41507a(21) =44687a(22) =51827a(23) =63587a(24) =64007a(25) =71987a(26) =73847a(27) =76367a(28) =76907a(29) =78467