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%I #15 Jan 02 2015 11:36:37
%S 2,16,102,528,2470,11016,47950,205792,874998,3694920,15519262,
%T 64899456,270415262,1123264408,4653525150,19234571968,79342610902,
%U 326704870152,1343120023678,5513861152000,22606830725598,92580354402712,378737813468542,1547884976787648
%N Number of n X n (0,1) matrices such that each row and each column is nondecreasing or nonincreasing.
%H Eric M. Schmidt, <a href="/A032260/b032260.txt">Table of n, a(n) for n = 1..1000</a>
%H Don Coppersmith, <a href="http://domino.research.ibm.com/Comm/wwwr_ponder.nsf/challenges/March2004.html">Ponder This: IBM Research Monthly Puzzles, March challenge</a>
%F a(n) = 2*n*(binomial(2*n, n)-n). G.f.: 4*x/(1-4*x)^(3/2)-2*x*(1+x)/(1-x)^3. - _Vladimir Baltic_ and _Vladeta Jovovic_, Jul 10 2003
%Y The number of n X n 0, 1 matrices such that each row and each column is increasing is in sequence A000984.
%Y Cf. A000984, A062528, A045992, A016742, A086113 - A086115.
%K nonn
%O 1,1
%A Yuval Dekel (dekelyuval(AT)hotmail.com), Jun 25 2003
%E Extended by _Vladimir Baltic_ and _Vladeta Jovovic_, Jul 10 2003
%E More terms from _Eric M. Schmidt_, May 01 2013
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