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%I
%S 7,14,15,21,23,28,30,31,35,39,42,45,46,47,49,55,56,60,62,69,70,71,75,
%T 77,78,79,84,87,90,91,92,93,94,95,98,103,110,111,112,115,117,120,124,
%U 127,133,138,140,141,142,143,147,150,151,154,155,156,158,159,167,168,174,180,182,183,184,186,188,190,191,196,199
%N Numbers having exactly 1 divisor of the form 8*k + 7.
%C A188172(a(n)) = 1;
%C A007522 is a subsequence.
%H _Reinhard Zumkeller_, <a href="/A141164/b141164.txt">Table of n, a(n) for n = 1..10000</a>
%e a(1) = A188226(1) = 7.
%t okQ[n_] := Length[Select[Divisors[n] - 7, Mod[#, 8] == 0 &]] == 1; Select[Range[200], okQ]
%o (Haskell)
%o import Data.List (elemIndices)
%o a141164 n = a141164_list !! (n-1)
%o a141164_list = map succ $ elemIndices 1 $ map a188172 [1..]
%Y Cf. A004771.
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, Mar 26 2011
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