A241366 Number of nX4 0..2 arrays with no element equal to fewer vertical neighbors than horizontal neighbors, with new values 0..2 introduced in row major order

4, 121, 4617, 169982, 6280325, 232173463, 8582759752, 317280724429, 11729003927933, 433589294151366, 16028613931818561, 592534154813233243, 21904372151717063740, 809744915865384534529, 29934061758919096085329

Offset

1,1

Comments

Column 4 of A241370

Links

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

Formula

Empirical: a(n) = 39*a(n-1) -89*a(n-2) +700*a(n-3) -7268*a(n-4) +12612*a(n-5) -23904*a(n-6) +125306*a(n-7) -773407*a(n-8) +79505*a(n-9) +3859531*a(n-10) -3389476*a(n-11) -9274781*a(n-12) +92305*a(n-13) +19760919*a(n-14) +25560786*a(n-15) -3646222*a(n-16) -31076228*a(n-17) -38721450*a(n-18) -14157300*a(n-19) +16466073*a(n-20) +30488603*a(n-21) +16120777*a(n-22) +778176*a(n-23) -4523626*a(n-24) -3303044*a(n-25) -267592*a(n-26) -1363088*a(n-27) -220864*a(n-28) +213504*a(n-29) -47104*a(n-30) +98304*a(n-31)

Example

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

Crossrefs

Sequence in context: A098839 A227525 A071129 * A358570 A263612 A033934

Adjacent sequences: A241363 A241364 A241365 * A241367 A241368 A241369

Keyword

nonn

Author

R. H. Hardin, Apr 20 2014

Status

approved