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A073123
a(n) is the largest number such that pi(a(n)) = prime(n).
2
4, 6, 12, 18, 36, 42, 60, 70, 88, 112, 130, 162, 180, 192, 222, 250, 280, 292, 336, 358, 372, 408, 432, 462, 520, 556, 568, 592, 600, 618, 718, 742, 786, 808, 862, 880, 928, 970, 996, 1032, 1068, 1090, 1162, 1180, 1212, 1222, 1300, 1422, 1438, 1450, 1480
OFFSET
1,1
COMMENTS
Primes with prime subscripts correspond to least numbers m, such that pi(m) = prime(n).
LINKS
FORMULA
a(n) = Max{x: A000720(x)=A000040(n)}.
a(n) = A000040(A000040(n)+1) - 1.
EXAMPLE
n=25: prime(25)=97; for 12 terms X = {509, 510, 511, 512, 513, 514, 515, 516, 517, 518, 519, 520}, pi(X)=97. Largest is a(25)=520, smallest is A006450(25), number of terms = A073124(25).
MAPLE
seq(ithprime(ithprime(n)+1)-1, n=1..100); # Robert Israel, May 14 2018
CROSSREFS
Equals A072677(n) - 1.
Sequence in context: A258838 A377067 A034425 * A079865 A059961 A027856
KEYWORD
nonn
AUTHOR
Labos Elemer, Jul 16 2002
EXTENSIONS
Edited by Robert Israel, May 14 2018
STATUS
approved