A202885 Number of nX4 0..2 arrays with every nonzero element less than or equal to some horizontal or vertical neighbor.

22, 1849, 109119, 6092872, 348151747, 19914296913, 1137589582096, 64992189188797, 3713325091122745, 212156302986486914, 12121270553957772787, 692534079965581463725, 39567093279061401381682, 2260617527909089482464661

Offset

1,1

Links

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

Formula

Empirical: a(n) = 58*a(n-1) -409*a(n-2) +19812*a(n-3) -7455*a(n-4) +2592909*a(n-5) +12335100*a(n-6) -16921246*a(n-7) -80782159*a(n-8) -4256903692*a(n-9) -15824503819*a(n-10) +51444732070*a(n-11) +665973079452*a(n-12) +1722193958142*a(n-13) -9381699323187*a(n-14) -52231180624458*a(n-15) -96373950069860*a(n-16) +536481249758489*a(n-17) +2646445223858022*a(n-18) -2670449971660545*a(n-19) -23685322388362288*a(n-20) +5273037676253028*a(n-21) +123562120872374900*a(n-22) +14554488540108224*a(n-23) -423772107328693168*a(n-24) -137361850647059616*a(n-25) +951983290636001856*a(n-26) +456183082446901248*a(n-27) -1309658113153668096*a(n-28) -798409204703133696*a(n-29) +997927647389908992*a(n-30) +720498553714114560*a(n-31) -407490029986775040*a(n-32) -334751276287918080*a(n-33) +70526354545704960*a(n-34) +67405719388815360*a(n-35)

Example

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

Crossrefs

Column 4 of A202889.

Sequence in context: A196705 A196854 A196948 * A183488 A253128 A046445

Adjacent sequences: A202882 A202883 A202884 * A202886 A202887 A202888

Keyword

nonn

Author

R. H. Hardin, Dec 25 2011

Status

approved