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A130133 Terms in A015922 not divisible by 3.

%I A130133 #16 Nov 02 2020 07:56:23
%S A130133 1,2,4,8,248,731,1333,3503,17608,35003,50963,62611,82603,90148,94643,
%T A130133 106978,201295,231311,253828,335723,364808,374573,425323,490915,
%U A130133 592595,628015,725203,984343,1031803,1112023,1136195,1376903,1411343,1430003,1642798,1926088
%N A130133 Terms in A015922 not divisible by 3.
%C A130133 Intersection of A015922 and A001651. - _Michel Marcus_, Oct 13 2013
%H A130133 Alois P. Heinz, <a href="/A130133/b130133.txt">Table of n, a(n) for n = 1..100</a>
%p A130133 a:= proc(n) option remember; local k;
%p A130133       for k from 1+`if`(n=1, 0, a(n-1)) while
%p A130133       irem(k, 3)=0 or 2&^k mod k <> 8 mod k do od; k
%p A130133     end:
%p A130133 seq(a(n), n=1..30);  # _Alois P. Heinz_, Jun 04 2014
%t A130133 {1, 2, 4, 8} ~Join~ Select[Range[2 10^6], PowerMod[2, #, #] == 8 && !Divisible[#, 3]&] (* _Jean-François Alcover_, Nov 02 2020 *)
%o A130133 (PARI) isok(n) = (n % 3) && (Mod(2^n, n) == Mod(8, n)); \\ _Michel Marcus_, Oct 13 2013
%Y A130133 Cf. A001651, A015922, A130134.
%Y A130133 Intersection with A033553 gives A277344.
%K A130133 nonn
%O A130133 1,2
%A A130133 _Zak Seidov_, May 12 2007
%E A130133 a(17)-a(28) from _Michel Marcus_, Oct 13 2013
%E A130133 a(29)-a(36) from _Alois P. Heinz_, Jun 04 2014