A230510 Number of nX3 0..7 arrays x(i,j) with each element horizontally or vertically next to at least one element with value (x(i,j)+1) mod 8, and upper left element zero

0, 0, 16, 170, 1716, 18588, 215314, 2510424, 29109876, 336208782, 3880077868, 44791093996, 517189418726, 5972202307652, 68962616646716, 796317295160910, 9195100866772220, 106176166673700588, 1226021261036004806

Offset

1,3

Comments

Column 3 of A230513

Links

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

Formula

Empirical: a(n) = 29*a(n-1) -335*a(n-2) +2077*a(n-3) -6996*a(n-4) +7187*a(n-5) +35989*a(n-6) -137298*a(n-7) +49203*a(n-8) +817380*a(n-9) -2714888*a(n-10) +4364152*a(n-11) -2602627*a(n-12) -2763225*a(n-13) +3140903*a(n-14) +774553*a(n-15) +7592822*a(n-16) -7936293*a(n-17) -11142093*a(n-18) -974062*a(n-19) +4597505*a(n-20) +9334934*a(n-21) +14314650*a(n-22) +13677366*a(n-23) +22812900*a(n-24) +23590128*a(n-25) +21169840*a(n-26) +15414200*a(n-27) +8471152*a(n-28) +3495872*a(n-29) +1140416*a(n-30) +251648*a(n-31) -38912*a(n-32)

Example

Some solutions for n=3
..0..7..6....0..1..0....0..1..2....0..3..4....0..1..2....0..1..2....0..7..4
..1..4..5....7..2..3....7..6..3....1..2..5....7..4..3....7..6..3....1..6..5
..2..3..4....6..5..4....4..5..4....0..7..6....6..5..2....6..5..4....2..3..4

Crossrefs

Sequence in context: A174645 A021424 A200673 * A238725 A221789 A018209

Adjacent sequences: A230507 A230508 A230509 * A230511 A230512 A230513

Keyword

nonn

Author

R. H. Hardin, Oct 21 2013

Status

approved