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Natural numbers having no valid Luhn mod 10 check digit.
3

%I #11 Oct 10 2019 09:58:09

%S 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,19,20,21,22,23,24,25,27,28,

%T 29,30,31,32,33,35,36,37,38,39,40,41,43,44,45,46,47,48,49,50,51,52,53,

%U 54,55,56,57,58,60,61,62,63,64,65,66,68,69,70,71,72,73

%N Natural numbers having no valid Luhn mod 10 check digit.

%C A249832(a(n)) = 0; A093017(a(n)) mod 10 > 0.

%H Reinhard Zumkeller, <a href="/A249830/b249830.txt">Table of n, a(n) for n = 1..10000</a>

%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Luhn_algorithm">Luhn algorithm</a>

%H <a href="/index/De#decimal_expansion">Index entries for sequences related to decimal expansion of n</a>

%o (Haskell)

%o a249830 n = a249830_list !! (n-1)

%o a249830_list = filter ((== 0) . a249832) [0..]

%Y Cf. A249832, A093017, A093018 (complement).

%K nonn

%O 1,2

%A _Reinhard Zumkeller_, Nov 08 2014