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%I #28 Mar 27 2018 05:51:18
%S 1,24,245,2484,24967,249934,2499755,24999435,249997579,2499995131,
%T 24999983109,249999976990
%N a(n) = number of primes that end in 1 among the first 10^n primes.
%F a(n) = A185705(A006988(n)). - _Michel Marcus_, Mar 20 2018
%e a(1) = 1 because the first 10 primes are 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, among which there is only one prime ending in 1.
%o (PARI) a(n) = #select(x->((x % 10) == 1), primes(10^n)); \\ _Michel Marcus_, Mar 07 2018
%Y Cf. A006988, A030430, A185705, A300398, A300399, A300400.
%K nonn,base,more
%O 1,2
%A _G. L. Honaker, Jr._, Mar 05 2018
%E a(3)-a(8) from Chuck Gaydos
%E a(9) from _Jon E. Schoenfield_, Mar 20 2018
%E a(10)-a(12) from _Giovanni Resta_, Mar 27 2018
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