A205417 - OEIS

%I #5 Mar 31 2012 12:37:06

%S 256,2768,31216,345008,3855292,42869296,477932092,5320759096,

%T 59277447518,660147565952,7353260497347,81897935985740,

%U 912200639448047,10160026458425994,113163447362993509,1260415842112508290

%N Number of (n+1)X2 0..3 arrays with the number of rightwards and downwards edge increases in each 2X2 subblock differing from the number in all its horizontal and vertical neighbors

%C Column 1 of A205422

%H R. H. Hardin, <a href="/A205417/b205417.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 84*a(n-2) +324*a(n-3) +684*a(n-4) +5414*a(n-5) +18901*a(n-6) +36870*a(n-7) +143492*a(n-8) +343938*a(n-9) +40768*a(n-10) -150414*a(n-11) -99939*a(n-12) -3297696*a(n-13) -11120072*a(n-14) -8376488*a(n-15) +15197186*a(n-16) +31001606*a(n-17) -11675195*a(n-18) -49570054*a(n-19) +20905770*a(n-20) +96572572*a(n-21) +51717035*a(n-22) -40813940*a(n-23) -122930663*a(n-24) -87507398*a(n-25) -11807220*a(n-26) +108567704*a(n-27) +71407480*a(n-28) -29180852*a(n-29) -82190628*a(n-30) -102278180*a(n-31) -79512996*a(n-32) -41480968*a(n-33) +7295869*a(n-34) +34396086*a(n-35) +22214484*a(n-36) +11734912*a(n-37) +5189888*a(n-38) -11136*a(n-39) -1300224*a(n-40) -656384*a(n-41) -147456*a(n-42) -16384*a(n-43) for n>44

%e Some solutions for n=4

%e ..3..0....2..0....0..1....1..3....1..1....2..0....1..0....1..1....3..1....3..2

%e ..1..1....0..1....0..0....1..0....1..1....3..1....0..0....3..3....1..2....2..0

%e ..2..2....3..2....1..1....0..1....2..1....1..0....0..3....3..2....0..3....2..3

%e ..2..2....2..0....3..0....0..2....2..3....0..2....1..2....0..1....0..0....0..0

%e ..1..2....3..0....0..3....3..2....0..0....0..3....1..0....2..1....0..0....2..3

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 27 2012