A206253 Number of (n+1)X7 0..3 arrays with every 2X2 subblock having zero permanent

258064, 434613664, 27285753856, 16533087493120, 2261195747329024, 848170637644693504, 173223627538782109696, 53060397281015908925440, 12918833834289527406198784, 3660962109260466462309744640

Offset

1,1

Comments

Column 6 of A206255

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

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)

Example

Some solutions for n=4
..3..1..0..0..1..3..0....1..1..3..2..3..2..0....3..0..0..1..0..2..0
..0..0..0..0..0..0..0....0..0..0..0..0..0..0....1..0..0..1..0..1..0
..2..3..1..0..3..2..0....3..2..3..0..1..0..2....2..0..0..3..0..0..0
..0..0..0..0..0..0..0....0..0..0..0..2..0..0....3..0..0..2..0..1..2
..1..0..3..1..0..1..2....1..1..1..0..1..0..2....0..0..0..2..0..0..0

Crossrefs

Sequence in context: A251883 A251165 A065794 * A157670 A252921 A216204

Adjacent sequences: A206250 A206251 A206252 * A206254 A206255 A206256

Keyword

nonn

Author

R. H. Hardin Feb 05 2012

Status

approved