|
%I #5 Mar 31 2012 12:36:56
%S 1,6,36,161,846,5545,35483,216488,1340730,8480848,53643799,338093942,
%T 2134537993,13508527719,85530509012,541535824313,3429939732074,
%U 21732616374723,137726568471728,872907436160530,5533065935012257
%N Number of nX2 0..5 arrays with every nonzero element less than or equal to at least two horizontal and vertical neighbors
%C Column 2 of A203338
%H R. H. Hardin, <a href="/A203332/b203332.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 21*a(n-1) -195*a(n-2) +1175*a(n-3) -5545*a(n-4) +21045*a(n-5) -64898*a(n-6) +173439*a(n-7) -400482*a(n-8) +801950*a(n-9) -1477586*a(n-10) +2342826*a(n-11) -3466079*a(n-12) +4698867*a(n-13) -5265061*a(n-14) +6840484*a(n-15) -5130611*a(n-16) +7218027*a(n-17) -3378370*a(n-18) +4680079*a(n-19) -2705514*a(n-20) -157208*a(n-21) -4245554*a(n-22) -4490128*a(n-23) -5765472*a(n-24) -5764538*a(n-25) -5166552*a(n-26) -4254715*a(n-27) -3098347*a(n-28) -2091098*a(n-29) -1271422*a(n-30) -706430*a(n-31) -357345*a(n-32) -162833*a(n-33) -67173*a(n-34) -24634*a(n-35) -7967*a(n-36) -2242*a(n-37) -526*a(n-38) -100*a(n-39) -14*a(n-40) -a(n-41)
%e Some solutions for n=4
%e ..0..0....2..2....4..4....3..3....1..1....5..5....5..5....2..2....2..2....0..0
%e ..3..3....2..2....4..4....4..4....1..1....5..5....5..5....5..5....5..5....2..2
%e ..5..5....1..1....2..2....5..5....2..2....5..5....5..5....5..5....5..5....4..4
%e ..5..5....0..0....2..2....5..5....2..2....5..5....1..1....5..5....5..5....4..4
%K nonn
%O 1,2
%A _R. H. Hardin_ Dec 31 2011
| 