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a(n) = smallest multiple of the n-th prime whose decimal expansion is nnn...n, or 0 if no such number exists.

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`%I #7 Mar 12 2015 23:54:07
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`%S 0,222,0,444444,55,666666,7777777777777777,888888888888888888,
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`%T 9999999999999999999999,1010101010101010101010101010,
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`%U 111111111111111111111111111111,121212,1313131313
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`%N a(n) = smallest multiple of the n-th prime whose decimal expansion is nnn...n, or 0 if no such number exists.
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`%C Conjecture: No entry is zero for n > 3.
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`%C No entry is zero for n > 3 because 10 is only divisible by the first and the third primes. In particular, for n>3 the number formed by nn..n (n-th prime - 1) n's is divisible by n-th prime. - _Sascha Kurz_, Jan 04 2003
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`%e a(6) = 666666 is the smallest multiple of 6th prime 13 using digit 6.
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`%K base,nonn
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`%O 1,2
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`%A _Amarnath Murthy_, Nov 24 2002
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`%E More terms from _Sascha Kurz_, Jan 04 2003
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