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%I #4 Dec 30 2013 16:40:14
%S 454,3980,28840,247394,1912554,16146124,127371542,1063565190,
%T 8483787204,70296753566,564722797390,4654352266800,37565456132170,
%U 308475061482182,2497492686007104,20457411426855534,165975465953392246
%N Number of (n+1)X(2+1) 0..4 arrays with 2X2 edge jumps all no more than +1 in one of the clockwise or counterclockwise directions but not both
%C Column 2 of A234777
%H R. H. Hardin, <a href="/A234771/b234771.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 9*a(n-1) +60*a(n-2) -657*a(n-3) -510*a(n-4) +14451*a(n-5) -9878*a(n-6) -143349*a(n-7) +195967*a(n-8) +711924*a(n-9) -1328829*a(n-10) -1738223*a(n-11) +4362370*a(n-12) +1713737*a(n-13) -7406892*a(n-14) +154943*a(n-15) +6781020*a(n-16) -1542017*a(n-17) -3326149*a(n-18) +1109694*a(n-19) +807890*a(n-20) -310656*a(n-21) -75048*a(n-22) +30144*a(n-23)
%e Some solutions for n=3
%e ..2..4..2....2..2..1....3..2..2....1..1..1....3..2..3....3..3..4....2..2..4
%e ..3..3..3....1..0..1....3..4..3....0..2..3....4..2..4....1..2..1....1..3..4
%e ..1..2..1....2..3..2....3..2..3....0..1..3....3..2..3....3..2..0....1..2..1
%e ..4..3..3....1..4..4....1..1..1....2..1..2....3..1..3....1..1..1....0..3..0
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 30 2013
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