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%I #13 Aug 19 2019 02:59:12
%S 3,126,186,399,924,1350,1386,1530,1806,2106,2646,2652,2814,2916,3066,
%T 3150,3654,3870,4662,4914,6162,6426,6846,6882,6930,7098,7566,7620,
%U 8190,8910,9270,10842,11076,12222,12870,14586,14910,15210,15246,15930,16506,17010
%N Numbers m such that the GCD of the x's that satisfy sigma(x)=m is 2.
%H Robert Israel, <a href="/A241647/b241647.txt">Table of n, a(n) for n = 1..1849</a>
%e We have sigma(68)=sigma(82)=126, and gcd(68, 82) = 2, hence 126 is in the sequence.
%e On the other hand, for x in [20, 26, 41], sigma(x)=42, and gcd(20, 26, 41)=1, hence 42 is not here, although gcd(20, 26) is 2.
%p N:= 10^5: # for terms <= N
%p V:= Vector(N):
%p for x from 1 to N do
%p s:= numtheory:-sigma(x);
%p if s <= N then
%p if V[s] = 0 then V[s]:= x
%p else V[s]:= igcd(V[s], x)
%p fi
%p fi
%p od: select(t -> V[t]=2, [$1..N]); # _Robert Israel_, Aug 18 2019
%Y Cf. A000203, A240667, A241625, A241646, A241647, A241648, A241649, A241650.
%K nonn
%O 1,1
%A _Michel Marcus_, Apr 26 2014
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