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%I #16 Jun 09 2024 09:05:03
%S 1,2,4,2,1,2,1,2,1,4,1,4,4,4,8,2,1,8,2,1,1,1,1,1,1,1,1,1,2,4,1,1,2,1,
%T 1,1,4,4,2,4,4,1,1,4,2,1,1,2,2,1,8,1,4,16,1,2,4,2,4,2,1,1,8,1,4,1,1,2,
%U 16,1,1,1,1,4,1,1,4,8,1,4,4,8,4,4,2,1,1,2,4,8,16,2
%N a(n) = gcd(2^n, pi(2^n)) = gcd(A000079(n), A007053(n)).
%t Table[GCD[2^n, PrimePi[2^n]], {n, 40}] (* _Michael De Vlieger_, Mar 25 2017 *)
%o (PARI) a(n) = gcd(2^n, primepi(2^n)); \\ _Michel Marcus_, Mar 26 2017
%Y Cf. A000720, A007053.
%K nonn
%O 1,2
%A _Labos Elemer_, Sep 16 2003
%E a(53)-a(92) from _Amiram Eldar_, Jun 09 2024