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A212176
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Row n of table lists exponents in canonical prime factorization of A181800(n) (n-th powerful number that is the first integer of its prime signature), in nonincreasing order.
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6
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2, 3, 4, 5, 2, 2, 6, 3, 2, 7, 4, 2, 3, 3, 8, 5, 2, 4, 3, 9, 6, 2, 5, 3, 2, 2, 2, 10, 7, 2, 4, 4, 6, 3, 3, 2, 2, 11, 8, 2, 5, 4, 7, 3, 4, 2, 2, 12, 9, 2, 6, 4, 3, 3, 2, 8, 3, 5, 2, 2, 5, 5, 13, 10, 2, 7, 4, 4, 3, 2, 9, 3, 6, 2, 2, 6, 5, 14, 11, 2, 8, 4, 5, 3, 2, 3
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OFFSET
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2,1
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COMMENTS
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LINKS
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FORMULA
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EXAMPLE
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Since 72 is a member of A181800, all positive exponents in its prime factorization (2^3*3^2) equal or exceed 2. Therefore, its second signature is the same as its prime signature, namely, {3,2} (nonincreasing version). Since 72 = A181800 (8), row 8 represents the prime signature and second signature {3,2}.
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CROSSREFS
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KEYWORD
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nonn,tabf
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AUTHOR
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STATUS
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approved
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