Number of Proth primes < 10^n.

Terms

a(0) =0a(1) =2a(2) =6a(3) =17a(4) =36a(5) =99a(6) =249a(7) =651a(8) =1774a(9) =5018a(10) =13587a(11) =39170a(12) =115968a(13) =323061a(14) =953827a(15) =2870277a(16) =8165537a(17) =24569821