a(1) = 1; then the smallest number such that both the forward and reverse n-th partial concatenation is a prime for n > 1. (Reverse concatenation is taken term-wise and not digit-wise.)

A083992

a(1) = 1; then the smallest number such that both the forward and reverse n-th partial concatenation is a prime for n > 1. (Reverse concatenation is taken term-wise and not digit-wise.)

Terms

    a(0) =1a(1) =1a(2) =3a(3) =11a(4) =13a(5) =47a(6) =67a(7) =213a(8) =99a(9) =753a(10) =861a(11) =143a(12) =2187a(13) =249a(14) =193a(15) =2957a(16) =14553a(17) =1557a(18) =2359a(19) =8669a(20) =1491a(21) =1003a(22) =12131a(23) =583a(24) =2643a(25) =3857a(26) =5631a(27) =999a(28) =9693a(29) =10231

External references