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A147963
a(n) = number of n-digit numbers not divisible by any of their digits.
1
0, 31, 244, 2012, 16831, 142224, 1212521, 10412937, 89964007, 781192156, 6812648578, 59632654665, 523659800584, 4611408084221, 40708677441051, 360148330033068, 3192319968308509, 28344332639409466, 252044515540416543, 2244223537121190033, 20006367211775121313
OFFSET
1,2
COMMENTS
Numbers ending in 0 are ignored.
LINKS
MATHEMATICA
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}]
CROSSREFS
Cf. A038772 Numbers not divisible by any of their digits.
Sequence in context: A344723 A284926 A321544 * A027846 A042872 A142623
KEYWORD
nonn,base
AUTHOR
Zak Seidov, Nov 17 2008
EXTENSIONS
a(10)-a(11) from Sean A. Irvine, Nov 11 2010
a(12) from Donovan Johnson, Nov 14 2010
a(13)-a(21) from Hiroaki Yamanouchi, Aug 31 2014
STATUS
approved