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A302490
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Fewest number of distinct prime factors in any product of a_1*a_2*...*a_t where n = a_1 < a_2 < ... < a_t = A006255(n) and the product is square.
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0
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0, 2, 2, 1, 2, 2, 2, 3, 1, 3, 3, 3, 3, 4, 3, 1, 2, 2, 2, 3, 3, 3, 2, 2, 1, 3, 4, 3, 2, 4, 2, 3, 5, 4, 4, 2, 3, 3, 3, 3, 3, 3, 3, 4, 3, 3, 3, 3, 1, 4, 4, 5, 3, 4, 5, 3, 4
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OFFSET
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1,2
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COMMENTS
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LINKS
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EXAMPLE
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a(14) = 4 because 14 * 15 * 16 * 18 * 20 * 21 has four distinct prime factors (2, 3, 5, and 7) and no other square product of a strictly increasing sequence starting at 14 and ending at 21 has fewer distinct prime factors.
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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