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A059469
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Numbers that are the products of distinct substrings of themselves.
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1
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110, 125, 210, 250, 310, 360, 375, 410, 510, 520, 610, 710, 735, 810, 910, 1000, 1010, 1020, 1030, 1040, 1050, 1060, 1070, 1080, 1090, 1100, 1110, 1197, 1210, 1250, 1280, 1296, 1310, 1352, 1410, 1510, 1520, 1593, 1610, 1710, 1734, 1750, 1810, 1910, 2010
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OFFSET
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1,1
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LINKS
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EXAMPLE
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a(1) = 110 = 11*10; a(10) = 520 = 52*5*2; a(13) = 735 = 35*7*3.
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MATHEMATICA
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okQ[n_] := Module[{dd, nn}, If[n == 1 || PrimeQ[n], Return[False]]; dd = IntegerDigits[n]; nn = FromDigits /@ Flatten[Table[dd[[i ;; j]], {i, 1, Length[dd]}, {j, i, Length[dd]}], 1] // Union // Most // Select[#, # != 0 && Divisible[n, #]&]&; MemberQ[Times @@@ Subsets[nn], n]];
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CROSSREFS
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KEYWORD
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nice,nonn,base
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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