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A175247
Primes (A000040) with noncomposite (A008578) subscripts.
2
2, 3, 5, 11, 17, 31, 41, 59, 67, 83, 109, 127, 157, 179, 191, 211, 241, 277, 283, 331, 353, 367, 401, 431, 461, 509, 547, 563, 587, 599, 617, 709, 739, 773, 797, 859, 877, 919, 967, 991, 1031, 1063, 1087, 1153, 1171, 1201, 1217, 1297, 1409, 1433, 1447
OFFSET
1,1
COMMENTS
A006450 is the main entry for these numbers. [Arkadiusz Wesolowski, Mar 12 2011]
FORMULA
a(n) U A007821(n+1) = A000040(n) for n >= 1. a(n) = prime(noncomposite(n)) = A000040(A008578(n)). a(1) = 2, a(n) = A006450(n-1) for n >= 2.
EXAMPLE
a(5) = 17 because a(5) = p(q(5)) = p(7) = 17, p = prime, q = noncomposite.
CROSSREFS
Sequence in context: A073021 A055498 A258185 * A298598 A079370 A014210
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Mar 13 2010
STATUS
approved