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%I #13 Jun 01 2022 19:55:17
%S 1,2,3,4,5,6,7,8,10,11,12,13,14,15,16,19,20,21,22,23,24,26,28,29,30,
%T 31,32,35,37,38,39,40,42,43,44,46,47,48,52,53,55,56,58,59,60,61,62,64,
%U 67,69,70,71,74,76,77,78,79,80,83,84,86,87,88,91,92,93,94,95,96
%N Numbers having exactly 1 divisor of the form 8*k + 1, that is, numbers with no divisor of the form 8*k + 1 other than 1.
%C Numbers not divisible by at least one of 9, 17, 25, ...
%H Jianing Song, <a href="/A343107/b343107.txt">Table of n, a(n) for n = 1..10000</a>
%e 7 is a term since it has no divisor congruent to 1 modulo 8 other than 1.
%t Select[Range[100],NoneTrue[Rest[Divisors[#]],Mod[#,8]==1&]&] (* _Harvey P. Dale_, Jun 01 2022 *)
%o (PARI) res(n,a,b) = sumdiv(n, d, (d%a) == b)
%o isA343107(n) = (res(n,8,1) == 1)
%Y Numbers having m divisors of the form 8*k + i: this sequence (m=1, i=1), A343108 (m=0, i=3), A343109 (m=0, i=5), A343110 (m=0, i=7), A343111 (m=2, i=1), A343112 (m=1, i=3), A343113 (m=1, i=5), A141164 (m=1, i=7).
%Y Indices of 1 in A188169.
%K nonn,easy
%O 1,2
%A _Jianing Song_, Apr 05 2021
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