A227163 Number of nX4 0,1 arrays indicating 2X2 subblocks of some larger (n+1)X5 binary array having a sum of one or less, with rows and columns of the latter in lexicographically nondecreasing order

5, 36, 193, 944, 4528, 20336, 85018, 330949, 1200425, 4071133, 12971110, 39024425, 111413038, 303209049, 789787118, 1975994532, 4763501990, 11094968344, 25028901331, 54804425836, 116706101674, 242125356042, 490174804573

Offset

1,1

Comments

Column 4 of A227165

Links

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

Formula

Empirical: a(n) = (1/1689515283456000)*n^19 + (1/42682491371520)*n^18 + (47/118562476032000)*n^17 + (289/10461394944000)*n^16 + (479/5230697472000)*n^15 + (7897/2092278988800)*n^14 + (1632263/10461394944000)*n^13 - (908693/603542016000)*n^12 + (896531/18289152000)*n^11 - (23306879/29262643200)*n^10 + (26023484833/1609445376000)*n^9 - (186161720861/804722688000)*n^8 + (2050542947543/871782912000)*n^7 - (5863470751207/392302310400)*n^6 + (78462384223117/1307674368000)*n^5 - (49466529613783/217945728000)*n^4 + (52739410297759/30875644800)*n^3 - (18770426920009/1715313600)*n^2 + (74837531735/2116296)*n - 43518 for n>8

Example

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

Crossrefs

Sequence in context: A272150 A271254 A358696 * A271055 A212329 A338487

Adjacent sequences: A227160 A227161 A227162 * A227164 A227165 A227166

Keyword

nonn

Author

R. H. Hardin Jul 03 2013

Status

approved