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%I #36 Oct 17 2023 07:38:23
%S 1,2,4,6,8,12,16,18,20,24,28,30,32,36,40,42,48,54,56,60,64,66,72,80,
%T 84,88,90,96,100,104,108,112,120,126,128,132,140,144,150,156,160,162,
%U 168,176,180,192,196,198,200,204,208,210,216,220,224,228,234,240,252,256
%N Practical numbers that have middle divisors.
%C Very similar to A174973 from which differs at a(195) = 1014 here and 1020 there.
%C It appears that these are also the practical numbers k whose symmetric representation of sigma(k) has an odd number of parts.
%e a(195) = 1014 is a practical number (A005153) and it has two middle divisors so 1014 is in the sequence.
%Y Intersection of A005153 and A071562.
%Y Cf. A067742, A174973, A236104, A237270, A237271, A237591, A237593, A317412.
%K nonn
%O 1,2
%A _Omar E. Pol_, Aug 30 2023