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%I #5 Mar 31 2012 12:36:46
%S 1,2,2,2,7,2,3,21,21,3,3,56,181,56,3,4,130,1341,1341,130,4,4,281,8312,
%T 29363,8312,281,4,5,555,44300,537572,537572,44300,555,5,5,1034,207562,
%U 8249505,29859761,8249505,207562,1034,5,6,1827,872998,108479344
%N T(n,k)=Number of nXk zero-sum -1..1 arrays with rows and columns lexicographically nondecreasing
%C Table starts
%C .1....2........2............3................3..................4
%C .2....7.......21...........56..............130................281
%C .2...21......181.........1341.............8312..............44300
%C .3...56.....1341........29363...........537572............8249505
%C .3..130.....8312.......537572.........29859761.........1387552127
%C .4..281....44300......8249505.......1387552127.......197324899476
%C .4..555...207562....108479344......54711391946.....23770010642604
%C .5.1034...872998...1248911674....1867753201968...2467219447235558
%C .5.1827..3348194..12812139620...56202066220732.224555987749683857
%C .6.3090.11857834.118772002152.1512619583145180
%H R. H. Hardin, <a href="/A202033/b202033.txt">Table of n, a(n) for n = 1..112</a>
%e Some solutions for n=2 k=7
%e .-1..0..0..0..0..1..1...-1.-1.-1..0..1..1..1...-1.-1..0..0..0..0..1
%e ..0.-1.-1.-1..0..1..1....0..0..1..0.-1..0..0....0..1.-1..0..0..0..1
%K nonn,tabl
%O 1,2
%A _R. H. Hardin_ Dec 09 2011