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%I #18 Nov 04 2013 12:19:17
%S 67,69,81,83,167,169,181,183,267,269,281,283,367,369,381,383,467,469,
%T 481,483,567,569,581,583,667,669,681,683,767,769,781,783,867,869,881,
%U 883,967,969,981,983,1067,1069,1081,1083,1167,1169,1181,1183,1267,1269
%N 8-ish numbers (end in 67, 69, 81, 83).
%H Reinhard Zumkeller, <a href="/A045808/b045808.txt">Table of n, a(n) for n = 1..1000</a>
%F Empirical G.f.: x*(67+2*x+12*x^2+2*x^3+17*x^4)/(1-x-x^4+x^5). [Colin Barker, Jan 23 2012]
%t Select[Range[1300],MemberQ[{67,69,81,83},Mod[#,100]]&] (* _Harvey P. Dale_, Jul 03 2013 *)
%o (Haskell)
%o import Data.List (findIndices)
%o a045808 n = a045808_list !! (n-1)
%o a045808_list = findIndices (`elem` [67,69,81,83]) $ cycle [0..99]
%o -- _Reinhard Zumkeller_, Jan 23 2012
%Y Cf. A045800-A045809.
%Y Cf. A045572, A045797, A045798.
%K nonn,base,easy
%O 1,1
%A _J. H. Conway_.
%E More terms from _Erich Friedman_.