A240286 Number of 3Xn 0..3 arrays with no element equal to one plus the sum of elements to its left or two plus the sum of the elements above it or zero plus the sum of the elements diagonally to its northwest, modulo 4

3, 19, 80, 570, 2574, 20764, 97348, 802835, 3797188, 31467286, 149131302, 1237084277, 5865347475, 48665192186, 230756350987, 1914691579848, 9079103009997, 75334276334445, 357222415759008, 2964076274068268

Offset

1,1

Comments

Row 3 of A240284

Links

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

Formula

Empirical: a(n) = 63*a(n-2) -1109*a(n-4) +7143*a(n-6) -395*a(n-8) -201246*a(n-10) +762860*a(n-12) +347011*a(n-14) -7366154*a(n-16) +11744674*a(n-18) +3758987*a(n-20) +10095295*a(n-22) -126415852*a(n-24) +204390541*a(n-26) -65238786*a(n-28) -59211883*a(n-30) -114625640*a(n-32) +381020006*a(n-34) -342073760*a(n-36) +16725276*a(n-38) +181283664*a(n-40) -110895680*a(n-42) +16492080*a(n-44) +1175136*a(n-46) +390464*a(n-48) for n>51

Example

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

Crossrefs

Sequence in context: A241885 A061171 A293561 * A163431 A167242 A373681

Adjacent sequences: A240283 A240284 A240285 * A240287 A240288 A240289

Keyword

nonn

Author

R. H. Hardin, Apr 03 2014

Status

approved