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A147963
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a(n) = number of n-digit numbers not divisible by any of their digits.
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1
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0, 31, 244, 2012, 16831, 142224, 1212521, 10412937, 89964007, 781192156, 6812648578, 59632654665, 523659800584, 4611408084221, 40708677441051, 360148330033068, 3192319968308509, 28344332639409466, 252044515540416543, 2244223537121190033, 20006367211775121313
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listen;
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OFFSET
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1,2
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COMMENTS
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Numbers ending in 0 are ignored.
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LINKS
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MATHEMATICA
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a[n_] := (c = 0; Do[id = IntegerDigits[i]; Le = Length[id]; pr = Product[If[id[[k]] > 0, Mod[i, id[[k]]], 1], {k, Le}]; If[Mod[i, 10]*pr > 0, (*Print[n]; *)c++ ], {i, 10^(n - 1), 10^n - 1}]; c); a[1] = 0; Table[a[m], {m, 8}]
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CROSSREFS
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Cf. A038772 Numbers not divisible by any of their digits.
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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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STATUS
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approved
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