A205929 - OEIS

%I #5 Mar 31 2012 12:37:07

%S 3036,95888,2554260,61330824,1380479280,29707151720,618727630440,

%T 12572031551824,250598068639404,4919732477995108,95406604751200868,

%U 1831743435192075704,34878586625734833808,659570280654009647388

%N Number of (n+1)X3 0..3 arrays with the number of clockwise edge increases in 2X2 subblocks nondecreasing rightwards and downwards

%C Column 2 of A205935

%H R. H. Hardin, <a href="/A205929/b205929.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 52*a(n-1) -932*a(n-2) +5759*a(n-3) +10849*a(n-4) -234078*a(n-5) +673409*a(n-6) +1202375*a(n-7) -11304831*a(n-8) +23922209*a(n-9) +7141603*a(n-10) -150135516*a(n-11) +339482733*a(n-12) -211293674*a(n-13) -467240307*a(n-14) +990904252*a(n-15) -659048383*a(n-16) +425605564*a(n-17) -598113326*a(n-18) -165307442*a(n-19) +218696702*a(n-20) +1926316092*a(n-21) -2363456104*a(n-22) +1299907647*a(n-23) -2290411338*a(n-24) +2999149296*a(n-25) -2677858528*a(n-26) +3240659104*a(n-27) -2449935969*a(n-28) -545304455*a(n-29) +2029623258*a(n-30) -1134447902*a(n-31) -328016504*a(n-32) +2291078682*a(n-33) -3555628280*a(n-34) +2334392768*a(n-35) +32937176*a(n-36) -1444968040*a(n-37) +1816104176*a(n-38) -1665496880*a(n-39) +1169138288*a(n-40) -651897744*a(n-41) +358320432*a(n-42) -210500256*a(n-43) +107715392*a(n-44) -44281920*a(n-45) +15223232*a(n-46) -3609472*a(n-47) +155904*a(n-48) +150528*a(n-49) -25600*a(n-50)

%e Some solutions for n=4

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Feb 01 2012