A206253 - OEIS

%I #5 Mar 31 2012 12:37:10

%S 258064,434613664,27285753856,16533087493120,2261195747329024,

%T 848170637644693504,173223627538782109696,53060397281015908925440,

%U 12918833834289527406198784,3660962109260466462309744640

%N Number of (n+1)X7 0..3 arrays with every 2X2 subblock having zero permanent

%C Column 6 of A206255

%H R. H. Hardin, <a href="/A206253/b206253.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 436*a(n-1) -20670912*a(n-3) +1768362192*a(n-4) +301989632832*a(n-5) -40539456253440*a(n-6) -1536342178669056*a(n-7) +377148789279765504*a(n-8) -1615023812548104192*a(n-9) -1758635101880092164096*a(n-10) +45109122367823348465664*a(n-11) +4303432979017649071128576*a(n-12) -181303558019449768187265024*a(n-13) -5085618071625131560739536896*a(n-14) +338719378543908534036612513792*a(n-15) +1447054855782983096105476030464*a(n-16) -323240313366898115796464692101120*a(n-17) +2430629740180983250878668715589632*a(n-18) +151402677346160235585093709301022720*a(n-19) -2307461851889299859661071648393527296*a(n-20) -28010992393774322798242500381933305856*a(n-21) +696331835357100763665844862341317918720*a(n-22) -69186082604013077340806446462997605908480*a(n-24) +353941433111056374606651926115966699700224*a(n-25)

%e Some solutions for n=4

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_ Feb 05 2012