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A259047
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Composite numbers which divide the concatenation of their prime factors, with multiplicity, in ascending order.
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10
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OFFSET
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1,1
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COMMENTS
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a(2) found by Jens Kruse Andersen, who also cleverly derived 119 large terms of the sequence from the factorization of numbers of the form 10^k+1 (see Links).
10^13 < a(4) <= 7810053011863508278028459 (the smallest of J. K. Andersen's large terms).
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LINKS
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EXAMPLE
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4373079629403 is equal to 3*367*2713*1464031 and it is a divisor of 336727131464031, hence it is in the sequence.
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CROSSREFS
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KEYWORD
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nonn,more,base,hard,bref
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AUTHOR
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STATUS
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approved
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