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A338361
Indices of primes in A283312.
3
2, 4, 6, 8, 12, 15, 19, 22, 26, 32, 35, 41, 45, 48, 52, 59, 65, 68, 74, 79, 82, 88, 92, 98, 106, 111, 114, 118, 121, 126, 139, 144, 150, 153, 162, 165, 172, 178, 182, 189, 195, 198, 209, 212, 216, 219, 230, 241, 245, 248, 253, 260, 263, 274, 280, 286, 293, 296, 302, 306, 309, 320, 333
OFFSET
1,1
LINKS
FORMULA
a(n) = p(n) + n - 1 - pi(p(n)/2), where p(n) = prime(n) and pi(i) = A000720(i).
MAPLE
with(NumberTheory);
A338361 := n -> ithprime(n)+n-1-pi(ithprime(n)/2);
MATHEMATICA
A338361[n_] := Prime[n] - PrimePi[Prime[n]/2] + n - 1;
Array[A338361, 100] (* Paolo Xausa, Jan 30 2024 *)
CROSSREFS
Sequence in context: A078327 A214415 A094109 * A090404 A015937 A058825
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Nov 03 2020
STATUS
approved