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Number of (n+1)X6 0..1 arrays with the sums of 2X2 subblocks nondecreasing rightwards and downwards
1

%I #5 Mar 31 2012 12:37:00

%S 676,5130,37642,189580,969528,3811097,15164049,50226272,167435933,

%T 488825091,1431119793,3794040002,10068045085,24759248822,60904889948,

%U 141191889755,327408688415,724682233233,1605043691566,3427407495669

%N Number of (n+1)X6 0..1 arrays with the sums of 2X2 subblocks nondecreasing rightwards and downwards

%C Column 5 of A204039

%H R. H. Hardin, <a href="/A204036/b204036.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 4*a(n-1) +36*a(n-2) -162*a(n-3) -604*a(n-4) +3154*a(n-5) +6186*a(n-6) -39306*a(n-7) -42019*a(n-8) +352234*a(n-9) +185034*a(n-10) -2417268*a(n-11) -373572*a(n-12) +13210560*a(n-13) -1570272*a(n-14) -59024568*a(n-15) +19656918*a(n-16) +219635712*a(n-17) -111911552*a(n-18) -689846188*a(n-19) +456557112*a(n-20) +1846825596*a(n-21) -1475810036*a(n-22) -4244002060*a(n-23) +3939977274*a(n-24) +8411721276*a(n-25) -8879451716*a(n-26) -14420754064*a(n-27) +17114577864*a(n-28) +21404362296*a(n-29) -28443491112*a(n-30) -27477002760*a(n-31) +40968113595*a(n-32) +30399541644*a(n-33) -51286804500*a(n-34) -28786717410*a(n-35) +55865954980*a(n-36) +23043376130*a(n-37) -52927725990*a(n-38) -15237886650*a(n-39) +43528988089*a(n-40) +7928932874*a(n-41) -30968624214*a(n-42) -2828143692*a(n-43) +18960199036*a(n-44) +237170744*a(n-45) -9916598664*a(n-46) +560142864*a(n-47) +4386822816*a(n-48) -514808256*a(n-49) -1619296704*a(n-50) +277582464*a(n-51) +489565056*a(n-52) -107579136*a(n-53) -118077184*a(n-54) +31074304*a(n-55) +21847296*a(n-56) -6606336*a(n-57) -2911744*a(n-58) +984064*a(n-59) +248832*a(n-60) -92160*a(n-61) -10240*a(n-62) +4096*a(n-63)

%e Some solutions for n=4

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 09 2012