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%I #11 Sep 01 2019 02:38:44
%S 1,1,2,4,8,13,23,42,70,114,178,313,479,759,1119,1858,2687,4207,5960,
%T 9468,13203,20198,27728,42955,58293,87333,117084,176706,234579,346450,
%U 455637,673619,878603,1276936,1652382,2404288,3089769,4429895,5654741,8105634
%N Number of pairs (lambda,mu) of partitions lambda of n and mu of ceiling(n/2) with mu <= lambda (by diagram containment).
%H Alois P. Heinz, <a href="/A303852/b303852.txt">Table of n, a(n) for n = 0..200</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/FerrersDiagram.html">Ferrers Diagram</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Ferrers_diagram">Ferrers diagram</a>
%F a(n) = A259478(n,ceiling(n/2)).
%Y Bisections give: A303861 (even part), A303863 (odd part).
%Y Cf. A259478.
%K nonn
%O 0,3
%A _Alois P. Heinz_, May 01 2018