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Number of nX6 binary arrays with rows and columns in nondecreasing order
1

%I #5 Mar 31 2012 12:35:56

%S 7,63,785,11819,183010,2625117,33345183,371484319,3651371519,

%T 32017940222,253426591764,1830279313811,12175210709509,75202293506213,

%U 434279600673295,2358572224659659,12108001563352798,59013152727127932

%N Number of nX6 binary arrays with rows and columns in nondecreasing order

%C Column 6 of A180985

%H R. H. Hardin, <a href="/A184141/b184141.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n)=64*a(n-1)-2016*a(n-2)+41664*a(n-3)-635376*a(n-4)+7624512*a(n-5)-74974368*a(n-6)+621216192*a(n-7)-4426165368*a(n-8)+27540584512*a(n-9)-151473214816*a(n-10)+743595781824*a(n-11)-3284214703056*a(n-12)+13136858812224*a(n-13)-47855699958816*a(n-14)+159518999862720*a(n-15)-488526937079580*a(n-16)+1379370175283520*a(n-17)-3601688791018080*a(n-18)+8719878125622720*a(n-19)-19619725782651120*a(n-20)+41107996877935680*a(n-21)-80347448443237920*a(n-22)+146721427591999680*a(n-23)-250649105469666120*a(n-24)+401038568751465792*a(n-25)-601557853127198688*a(n-26)+846636978475316672*a(n-27)-1118770292985239888*a(n-28)+1388818294740297792*a(n-29)-1620288010530347424*a(n-30)+1777090076065542336*a(n-31)-1832624140942590534*a(n-32)+1777090076065542336*a(n-33)-1620288010530347424*a(n-34)+1388818294740297792*a(n-35)-1118770292985239888*a(n-36)+846636978475316672*a(n-37)-601557853127198688*a(n-38)+401038568751465792*a(n-39)-250649105469666120*a(n-40)+146721427591999680*a(n-41)-80347448443237920*a(n-42)+41107996877935680*a(n-43)-19619725782651120*a(n-44)+8719878125622720*a(n-45)-3601688791018080*a(n-46)+1379370175283520*a(n-47)-488526937079580*a(n-48)+159518999862720*a(n-49)-47855699958816*a(n-50)+13136858812224*a(n-51)-3284214703056*a(n-52)+743595781824*a(n-53)-151473214816*a(n-54)+27540584512*a(n-55)-4426165368*a(n-56)+621216192*a(n-57)-74974368*a(n-58)+7624512*a(n-59)-635376*a(n-60)+41664*a(n-61)-2016*a(n-62)+64*a(n-63)-a(n-64) (=polynomial degree 63)

%e Some solutions for 3X6

%e ..0..0..0..1..1..1....0..0..0..0..1..1....0..0..0..1..1..1....0..1..1..1..1..1

%e ..0..0..1..0..0..1....0..0..0..1..0..1....0..0..1..0..0..1....1..0..1..1..1..1

%e ..0..1..1..0..1..1....0..0..0..1..1..1....1..1..1..0..0..1....1..1..0..0..0..0

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 09 2011