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A070844
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a(n) = smallest n-digit number with exactly n divisors, or 0 if no such number exists.
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6
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1, 11, 121, 1003, 14641, 100017, 1771561, 10000005, 100020001, 1000000016, 25937424601, 100000000004, 3138428376721, 10000000001344, 100000720001296, 1000000000000006, 45949729863572161, 100000000000000404
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OFFSET
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1,2
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LINKS
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FORMULA
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If n is a prime < 29 then a(n) = 11^(n-1). - Chandler
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MATHEMATICA
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For[n=1, n<10, n++, k := 10^(n-1); While[Not[Length[Divisors[k]] == n], k++ ]; Print[k]] (Steinerberger)
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CROSSREFS
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KEYWORD
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base,nonn
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AUTHOR
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EXTENSIONS
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a(6) confirmed by Antonio G. Astudillo (afg_astudillo(AT)lycos.com), Apr 08 2003
a(15) corrected, and a(11)-a(14), a(16)-a(18) confirmed by Ray Chandler, Feb 10 2009
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STATUS
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approved
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