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A067791
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Smallest multidigit prime such that the sum of the squares of its digits is equal to n times the product of its digits, or 0 if no such prime exists.
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1
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11353, 11, 211, 1111116211, 11411, 511111, 1111111111111111111111111111213, 11111117, 111111181, 1111111111111111111711, 2111111111111111111, 111111111111111121111, 1111111111111111111111141111111111111, 1111111111111111211111111
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OFFSET
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1,1
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COMMENTS
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Sum(xi^2) = n*Product(xi) where xi is the i-th digit of a prime in base 10. The zero has been entered for those n values such that no solution has been found up to 10^7.
No more terms up to 4.4*10^11.
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LINKS
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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EXTENSIONS
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a(4), a(7), a(10)-a(17), a(19), a(21) and a(23) from Donovan Johnson, Nov 20 2010
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STATUS
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approved
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