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%I #6 Feb 15 2023 21:48:18
%S 2,4,6,4,10,5,14,4,6,7,22,5,26,9,8,4,34,5,38,7,10,13,46,5,10,15,6,9,
%T 58,6,62,4,14,19,12,5,74,21,16,7,82,6,86,13,8,25,94,5,14,7,20,15,106,
%U 5,16,9,22,31,118,6,122,33,10,4,18,6,134,19,26,10,142,5
%N Two times the median of the set of distinct prime factors of n; a(1) = 2.
%C The median of a multiset is either the middle part (for odd length), or the average of the two middle parts (for even length). Since the denominator is always 1 or 2, the median can be represented as an integer by multiplying by 2.
%e The prime factors of 336 are {2,2,2,2,3,7}, with distinct parts {2,3,7}, with median 3, so a(336) = 6.
%t Table[2*Median[First/@FactorInteger[n]],{n,100}]
%Y The union is 2 followed by A014091, complement of A014092.
%Y Distinct prime factors are listed by A027748.
%Y The version for divisors is A063655.
%Y Positions of odd terms are A100367.
%Y For mean instead of two times median we have A323171/A323172.
%Y The version for prime indices is A360005.
%Y The version for distinct prime indices is A360457.
%Y The version for prime factors is A360459.
%Y The version for prime multiplicities is A360460.
%Y Positions of even terms are A360552.
%Y The version for 0-prepended differences is A360555.
%Y A112798 lists prime indices, length A001222, sum A056239.
%Y A304038 lists distinct prime indices.
%Y A359893 and A359901 count partitions by median, odd-length A359902.
%Y Cf. A000975, A026424, A078174, A316413, A325347, A359907, A360006, A360248, A360453, A360550, A360551.
%K nonn
%O 1,1
%A _Gus Wiseman_, Feb 14 2023