Total number of palindromic primes in base 4 below 4^n.

Terms

a(0) =2a(1) =3a(2) =6a(3) =6a(4) =16a(5) =16a(6) =45a(7) =45a(8) =142a(9) =142a(10) =435a(11) =435a(12) =1417a(13) =1417a(14) =4802a(15) =4802a(16) =16433a(17) =16433a(18) =57808a(19) =57808a(20) =210708a(21) =210708a(22) =752233a(23) =752233a(24) =2748264a(25) =2748264a(26) =10211513a(27) =10211513a(28) =38013234a(29) =38013234