Upper bound of twin prime pairs whose digital reverse is prime.

Terms

a(0) =5a(1) =7a(2) =13a(3) =31a(4) =73a(5) =151a(6) =181a(7) =199a(8) =313a(9) =1021a(10) =1033a(11) =1153a(12) =1231a(13) =1279a(14) =1321a(15) =1429a(16) =1453a(17) =1669a(18) =1723a(19) =1789a(20) =1879a(21) =1933a(22) =3121a(23) =3169a(24) =3301a(25) =3373a(26) =3391a(27) =3463a(28) =3469a(29) =3541