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Number of (n+1)X(2+1) 0..2 arrays with the maximum plus the minimum minus the lower median of every 2X2 subblock equal
1

%I #4 Jan 31 2014 07:18:32

%S 327,2211,15254,109205,786609,5747502,42215123,312592339,2324534826,

%T 17376767995,130331607713,981030661960,7403192678283,56006537652545,

%U 424502700379214,3223178794593881,24506960972636245,186565676015487922

%N Number of (n+1)X(2+1) 0..2 arrays with the maximum plus the minimum minus the lower median of every 2X2 subblock equal

%C Column 2 of A236828

%H R. H. Hardin, <a href="/A236822/b236822.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 20*a(n-1) -74*a(n-2) -950*a(n-3) +7675*a(n-4) +5902*a(n-5) -208583*a(n-6) +358712*a(n-7) +2437168*a(n-8) -8245218*a(n-9) -11507689*a(n-10) +77981588*a(n-11) -13353740*a(n-12) -390127858*a(n-13) +398463912*a(n-14) +1060576100*a(n-15) -1911844548*a(n-16) -1338399672*a(n-17) +4592202520*a(n-18) -205399632*a(n-19) -6115028512*a(n-20) +2874814400*a(n-21) +4321062784*a(n-22) -3582260416*a(n-23) -1253904064*a(n-24) +1886965760*a(n-25) -92450688*a(n-26) -394737408*a(n-27) +90316800*a(n-28) +17190912*a(n-29) -4915200*a(n-30)

%e Some solutions for n=4

%e ..0..1..2....1..2..0....2..0..0....2..1..0....2..1..0....2..1..0....2..0..1

%e ..1..0..1....1..2..0....2..1..1....0..2..2....2..2..1....1..0..1....2..1..2

%e ..1..0..1....0..0..0....2..2..0....1..2..1....0..1..0....1..2..2....0..2..0

%e ..0..0..0....1..2..1....0..1..2....0..1..0....1..0..1....2..0..1....1..2..1

%e ..0..1..1....2..1..2....0..0..2....2..2..2....2..2..1....1..2..2....2..0..1

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 31 2014