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A089298
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Smallest prime with digit product 10^n.
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5
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11, 251, 14551, 155581, 4545551, 45555581, 555555881, 44555555581, 455555558581, 5555555888551, 255555555585881, 14555555558558851, 155555555858885551, 2555555555558885851, 45555555555585855881
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OFFSET
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0,1
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COMMENTS
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These numbers may not contain the digits {0, 3, 6, 7 or 9} and must end with the digit 1. Also the number of 2's plus half the number of 4's plus a quarter of the number of 8's must equal the number of 5's which in turn must equal n. - Robert G. Wilson v, Nov 06 2003
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LINKS
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EXAMPLE
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a(4) = 4545551 and the digit product = 10^4.
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MATHEMATICA
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NextPrim[n_] := Block[{k = n + 1}, While[ !PrimeQ[k], k++ ]; k]; a = Table[0, {10}]; p = 2; Do[ q = Log[10, Times @@ IntegerDigits[p]]; If[q != 0 && IntegerQ[q] && a[[q]] == 0, a[[q]] = p; Print[q, " = ", p]]; p = NextPrim[p], {n, 1, 10^9}]; a
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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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STATUS
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approved
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