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A230460
Prime(2*prime(n)).
5
7, 13, 29, 43, 79, 101, 139, 163, 199, 271, 293, 373, 421, 443, 491, 577, 647, 673, 757, 821, 839, 929, 983, 1061, 1181, 1231, 1277, 1307, 1361, 1429, 1609, 1667, 1759, 1789, 1973, 1997, 2083, 2161, 2243, 2339, 2411, 2441, 2633, 2663, 2707, 2729, 2917
OFFSET
1,1
COMMENTS
A subsequence of A031378 (subsequence of A031215) and of A106349, which are both subsequences of A007821 which is the complement of A006450 in the primes A000040.
LINKS
FORMULA
a(n) ~ 2n log(n) log(2n log(n)) ~ 2n (log n)^2.
a(n) = A000040(A100484(n)). - Omar E. Pol, Oct 19 2013
EXAMPLE
a(3) = 29 because the third prime is 5, and 2 * 5 = 10, and then we see that the tenth prime is 29.
a(4) = 43 because the fourth prime is 7, and 2 * 7 = 14, and then we see that the fourteenth prime is 43.
MATHEMATICA
Prime[2Prime[Range[50]]] (* Alonso del Arte, Oct 19 2013 *)
PROG
(PARI) A230460=n->prime(2*prime(n))
CROSSREFS
Cf. A217622.
Sequence in context: A283650 A045463 A082221 * A182624 A096333 A133325
KEYWORD
nonn,easy
AUTHOR
M. F. Hasler, Oct 19 2013
STATUS
approved