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%I #9 Sep 01 2019 02:39:42
%S 1,4,13,42,114,313,759,1858,4207,9468,20198,42955,87333,176706,346450,
%T 673619,1276936,2404288,4429895,8105634,14576610,26017631,45767924,
%U 79970030,137934105,236375455,400667547,674818625,1125626097,1866565406,3068368925,5015847315
%N Number of pairs (lambda,mu) of partitions lambda of 2n+1 and mu of n+1 with mu <= lambda (by diagram containment).
%H Alois P. Heinz, <a href="/A303863/b303863.txt">Table of n, a(n) for n = 0..100</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(2n+1,n+1) = A303852(2n+1).
%Y Bisection (odd part) of A303852.
%Y Cf. A259478.
%K nonn
%O 0,2
%A _Alois P. Heinz_, May 01 2018