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A361665
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Number of ordered factorizations of p_1^x_1 * ... * p_k^x_k, where (x_1, ..., x_k) is the partition with Heinz number n and p_1, ..., p_k are distinct primes.
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3
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1, 1, 2, 3, 4, 8, 8, 13, 26, 20, 16, 44, 32, 48, 76, 75, 64, 176, 128, 132, 208, 112, 256, 308, 252, 256, 818, 368, 512, 604, 1024, 541, 544, 576, 768, 1460, 2048, 1280, 1376, 1076, 4096, 1888, 8192, 976, 3172, 2816, 16384, 2612, 2568, 2316, 3392, 2496, 32768
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OFFSET
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1,3
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COMMENTS
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Also, a(n) is the number of paths from (0, ..., 0) to P in which each step adds a nonnegative integer to each coordinate (and a positive number to at least one coordinate), where P is the partition with Heinz number n.
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LINKS
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FORMULA
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EXAMPLE
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The partition with Heinz number 6 is (1,2), and p^1*q^2 has 8 ordered factorizations, where p and q are distinct primes, so a(6) = 8. With p = 3 and q = 2, for example, we have the 8 = A074206(12) factorizations 12 = 2*6 = 3*4 = 4*3 = 6*2 = 2*2*3 = 2*3*2 = 3*2*2.
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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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