%I #15 Aug 17 2021 06:25:55
%S 1,15,20,39,44,58,63,77,82,96,100,119,124,138,143,157,162,176,181,195,
%T 204,218,223,237,242,256,261,275,280,299,303,317,322,336,341,355,360,
%U 379,384,398,402,416,421,435,440,459,464,478,483,497,505,510,529,534
%N Indices of terms in A093019 with value 8.
%C Integers which require a following 8 to have a valid Luhn mod 10 check digit.
%H Reinhard Zumkeller, <a href="/A093028/b093028.txt">Table of n, a(n) for n = 1..10000</a>
%H John Kilgo, <a href="https://web.archive.org/web/20040627030859/http://www.dotnetjohn.com/articles/articleid97.aspx">Using the Luhn Algorithm</a>, DotNetJohn.com.
%H Webopedia, <a href="http://www.webopedia.com/TERM/L/Luhn_formula.html">Luhn formula</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>
%F A093019(a(n)) = 8. - _Reinhard Zumkeller_, Nov 08 2014
%e 15 is in the sequence because A093019(15)=8; 158 has a valid Luhn mod 10 check digit.
%o (Haskell)
%o a093028 n = a093028_list !! (n-1)
%o a093028_list = filter ((== 8) . a093019) [0..]
%o -- _Reinhard Zumkeller_, Nov 08 2014
%Y Cf. A093017-A093029.
%K easy,nonn,base
%O 1,2
%A _Ray Chandler_, Apr 03 2004
%E Offset changed by _Reinhard Zumkeller_, Nov 08 2014