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A177951
PrimePi(A066903(n)), the index of A066903(n) in the primes.
0
4, 1, 3, 2, 8, 7, 7, 4, 4, 9, 3, 6, 6, 29, 10, 5, 5, 5, 8, 8, 8, 8, 28, 28, 7, 7, 7, 7, 30, 30, 30, 4, 13, 13, 27, 27, 9, 9, 9, 9, 9, 9, 9, 19, 11, 11, 11, 11, 11, 11, 6, 6, 6, 6, 26, 26, 6, 6, 31, 23, 31, 15, 15, 29, 15, 29, 29, 29, 15, 15, 10, 10, 10, 10, 10, 10, 10, 10, 10, 21, 12, 12, 12
OFFSET
1,1
FORMULA
a(n) = A000720(A066903(n)) = A049084(A066903(n)) . [R. J. Mathar, May 28 2010]
EXAMPLE
a(14)= 29 because prime(29) = 109, and A066903(14) = 109.
CROSSREFS
Sequence in context: A342403 A019633 A067277 * A222130 A061903 A309603
KEYWORD
nonn
AUTHOR
Michel Lagneau, May 15 2010
EXTENSIONS
Clearer definition from R. J. Mathar, May 28 2010
STATUS
approved