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A336965
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a(n) is the product of the distinct prime numbers appearing in the prime tower factorization of n.
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2
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1, 2, 3, 2, 5, 6, 7, 6, 6, 10, 11, 6, 13, 14, 15, 2, 17, 6, 19, 10, 21, 22, 23, 6, 10, 26, 3, 14, 29, 30, 31, 10, 33, 34, 35, 6, 37, 38, 39, 30, 41, 42, 43, 22, 30, 46, 47, 6, 14, 10, 51, 26, 53, 6, 55, 42, 57, 58, 59, 30, 61, 62, 42, 6, 65, 66, 67, 34, 69, 70
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OFFSET
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1,2
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COMMENTS
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The prime tower factorization of a number is defined in A182318.
For any n > 0, a(n) is the product of the terms in n-th row of A336964.
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LINKS
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EXAMPLE
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a(n) = n iff n is squarefree (A005117).
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PROG
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(PARI) a(n) = { my (f=factor(n), v=vecprod(f[, 1]~)); for (k=1, #f~, v=lcm(v, a(f[k, 2]))); v }
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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