A316991 - OEIS

%I #10 Aug 08 2018 23:29:07

%S 6,10,12,18,20,21,22,24,26,30,34,35,36,38,40,42,44,46,48,50,52,54,58,

%T 60,62,63,66,68,70,72,74,76,77,78,80,82,84,86,88,90,91,92,94,96,100,

%U 102,104,105,106,108,110,114,116,118,119,120,122,124,126,130,132

%N Numbers m such that 1 < gcd(m, 14) < m and m does not divide 14^e for e >= 0.

%C Complement of A000027 and union of A003591 and A162699.

%C Analogous to A081062 and A105115 that apply to A120944(1) and A120944(2), respectively.

%C This sequence applies to A120944(3).

%H Michael De Vlieger, <a href="/A316991/b316991.txt">Table of n, a(n) for n = 1..10000</a>

%e 6 is in the sequence since gcd(6, 14) = 2 and 6 does not divide 14^e with integer e >= 0.

%e 2 is not in the sequence since 2 | 14.

%e 4 is not in the sequence since 4 | 14^2.

%e 3 and 5 are not in the sequence since they are coprime to 14.

%t With[{nn = 132, k = 14}, Select[Range@ nn, And[1 < GCD[#, k] < #, PowerMod[k, Floor@ Log2@ nn, #] != 0] &]]

%Y Cf. A003591, A081062, A105115, A120944, A162699.

%K easy,nonn

%O 1,1

%A _Michael De Vlieger_, Aug 02 2018