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A212639
Number of prime factors of A181800(n) (n-th powerful number that is the first integer of its prime signature), counted with multiplicity.
2
0, 2, 3, 4, 5, 4, 6, 5, 7, 6, 6, 8, 7, 7, 9, 8, 8, 6, 10, 9, 8, 9, 7, 11, 10, 9, 10, 8, 12, 11, 10, 8, 11, 9, 10, 13, 12, 11, 9, 12, 10, 11, 14, 13, 12, 10, 9, 13, 11, 12, 10, 15, 14, 13, 11, 8, 12, 10, 14, 12, 13, 11, 16, 15, 14, 12, 9, 13, 11, 15, 13, 14, 12
OFFSET
1,2
COMMENTS
Every nonnegative integer n appears A002865(n) times.
LINKS
FORMULA
a(n) = A001222(A181800(n)).
EXAMPLE
72 (2^3*3^2, or 2*2*2*3*3) has a total of 5 prime factors when repetitions are counted. Since 72 = A181800(8), a(8) = 5.
CROSSREFS
KEYWORD
nonn
AUTHOR
Matthew Vandermast, Jun 09 2012
STATUS
approved