Total number of palindromic primes in base 5 below 5^n.

Terms

a(0) =2a(1) =2a(2) =7a(3) =7a(4) =25a(5) =25a(6) =83a(7) =83a(8) =243a(9) =243a(10) =1038a(11) =1038a(12) =4205a(13) =4205a(14) =17724a(15) =17724a(16) =78553a(17) =78553a(18) =349246a(19) =349246a(20) =1526658a(21) =1526658a(22) =7028772a(23) =7028772a(24) =32055014a(25) =32055014a(26) =146939924a(27) =146939924