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%I #12 Sep 17 2019 02:36:20
%S 1,2,2,2,11,30,84,254,717,1500,13035,44550,300950,1505504,3854579,
%T 14283372,83480149,251709276,3136016690,12605049160,162391467080,
%U 691231886400,3678703702014,23362113269002,94834621131920,374452713892530,4019520663745860,15252585773825400
%N Twice the median of {Stirling2(n, k), k = 0..n}.
%C "Twice" is included in the definition to handle half-integer medians.
%H Vaclav Kotesovec, <a href="/A327559/b327559.txt">Table of n, a(n) for n = 1..700</a>
%H Vaclav Kotesovec, <a href="/A327559/a327559.jpg">Plot of a(n)/a(n-1) for n = 2..1000</a>
%e For n = 6, {Stirling2(6, k), k = 0..6} = {0, 1, 31, 90, 65, 15, 1}, so we have 3 elements {0, 1, 1} that are < 15, and 3 elements {31, 90, 65} that are > 15. Hence, 15 is the median, and a(6) = 2*15 = 30.
%p a:= n->(l->l[floor(1+n/2)]+l[ceil(1+n/2)])(sort([seq(Stirling2(n, j), j=0..n)])):
%p seq(a(n), n=1..30); # _Alois P. Heinz_, Sep 16 2019
%t Table[2 Median[Table[StirlingS2[n, k], {k, 0, n}]], {n, 1, 30}]
%o (PARI) a(n)={my(t=vecsort(vector(n+1, k, stirling(n,k-1,2)))); t[n\2+1] + t[n-n\2+1]} \\ _Andrew Howroyd_, Sep 16 2019
%K nonn,easy
%O 1,2
%A _Vladimir Reshetnikov_, Sep 16 2019
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