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Number of (n+1)X3 0..2 arrays with every 2X2 subblock diagonal sum less antidiagonal sum equal to some horizontal or vertical neighbor 2X2 subblock diagonal sum less antidiagonal sum
1

%I #7 Mar 31 2012 12:36:02

%S 99,697,4451,30775,207705,1418183,9658679,65903901,449371311,

%T 3065504279,20907068253,142616273243,972755259615,6635544380685,

%U 45262083721743,308751947312775,2106102500275185,14366708767138979,98001661767659167

%N Number of (n+1)X3 0..2 arrays with every 2X2 subblock diagonal sum less antidiagonal sum equal to some horizontal or vertical neighbor 2X2 subblock diagonal sum less antidiagonal sum

%C Column 2 of A185504

%H R. H. Hardin, <a href="/A185499/b185499.txt">Table of n, a(n) for n = 1..200</a>

%F Empirical: a(n)=16*a(n-1)-66*a(n-2)-134*a(n-3)+1443*a(n-4)-2944*a(n-5)+4970*a(n-6)-14851*a(n-7)-11571*a(n-8)+61044*a(n-9)+159738*a(n-10)+413413*a(n-11)-2914428*a(n-12)-2469514*a(n-13)+6557377*a(n-14)+39589072*a(n-15)+22764483*a(n-16)-206879740*a(n-17)-346733427*a(n-18)+278776495*a(n-19)+1495676084*a(n-20)+2695509571*a(n-21)-4686678083*a(n-22)-7299225497*a(n-23)+6056115083*a(n-24)-16127233866*a(n-25)-88281813514*a(n-26)-7261550680*a(n-27)+1088424262105*a(n-28)+899731654396*a(n-29)-3245433499238*a(n-30)-7815484803768*a(n-31)-406652905248*a(n-32)+22811862007908*a(n-33)+22421132651472*a(n-34)-15498436106752*a(n-35)-12123613528560*a(n-36)-10766636743176*a(n-37)-5067935559232*a(n-38)-408175178563744*a(n-39)-32063168173376*a(n-40)+11604755392032*a(n-41)+674372049197920*a(n-42)+1660897630461888*a(n-43)+3566535713014464*a(n-44)-377394253895680*a(n-45)-1288439207533312*a(n-46)-10038152022954496*a(n-47)-16065995298211328*a(n-48)-17310921165163520*a(n-49)-7179507436965888*a(n-50)+9381015453671424*a(n-51)+65340992207912960*a(n-52)+65285348845109248*a(n-53)+92246407919616000*a(n-54)+129518737725161472*a(n-55)-10289528873484288*a(n-56)-278577260634832896*a(n-57)-222025407375605760*a(n-58)-108195623685586944*a(n-59)-215332645430624256*a(n-60)-241001042326585344*a(n-61)+66507208516435968*a(n-62)+264107131416870912*a(n-63)+164236535305076736*a(n-64)+145690315255185408*a(n-65)+161037241144049664*a(n-66)+51643863923687424*a(n-67)-99781853552050176*a(n-68)-113923742849040384*a(n-69)-40634522378698752*a(n-70)+14258715897102336*a(n-71)+17583870987730944*a(n-72)+5072270477230080*a(n-73)

%e Some solutions for 5X3

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Jan 29 2011