Total number of palindromic primes in base 7 below 7^n.

Terms

a(0) =3a(1) =3a(2) =9a(3) =9a(4) =50a(5) =50a(6) =204a(7) =204a(8) =1135a(9) =1135a(10) =6086a(11) =6086a(12) =36018a(13) =36018a(14) =216932a(15) =216932a(16) =1306070a(17) =1306070a(18) =8129138a(19) =8129138a(20) =51773946a(21) =51773946a(22) =326701423a(23) =326701423