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%I #16 Jan 30 2024 11:42:21
%S 2,4,6,8,12,15,19,22,26,32,35,41,45,48,52,59,65,68,74,79,82,88,92,98,
%T 106,111,114,118,121,126,139,144,150,153,162,165,172,178,182,189,195,
%U 198,209,212,216,219,230,241,245,248,253,260,263,274,280,286,293,296,302,306,309,320,333
%N Indices of primes in A283312.
%H N. J. A. Sloane, <a href="/A338361/b338361.txt">Table of n, a(n) for n = 1..7099</a>
%F a(n) = p(n) + n - 1 - pi(p(n)/2), where p(n) = prime(n) and pi(i) = A000720(i).
%p with(NumberTheory);
%p A338361 := n -> ithprime(n)+n-1-pi(ithprime(n)/2);
%t A338361[n_] := Prime[n] - PrimePi[Prime[n]/2] + n - 1;
%t Array[A338361, 100] (* _Paolo Xausa_, Jan 30 2024 *)
%Y Cf. A000720, A283312.
%K nonn
%O 1,1
%A _N. J. A. Sloane_, Nov 03 2020