A230613 Number of n X 7 0..2 arrays x(i,j) with each element horizontally or antidiagonally next to at least one element with value (x(i,j)+1) mod 3, and upper left element zero.

0, 108, 20430, 3023532, 434369516, 62312057642, 8937075346246, 1281770005911328, 183833260079110226, 26365619477959488238, 3781393362413307038662, 542332629952247633325852

Offset

1,2

Comments

Column 7 of A230614.

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n) = 227*a(n-1) -15073*a(n-2) +516849*a(n-3) -12004704*a(n-4) +210898965*a(n-5) -2423644215*a(n-6) +10342524170*a(n-7) +95146925330*a(n-8) -1270472692024*a(n-9) +3509210149862*a(n-10) +18487113129390*a(n-11) -118346116978076*a(n-12) -142045747219349*a(n-13) +1981657241253047*a(n-14) -797608174902841*a(n-15) -15665230743026270*a(n-16) +16136528041550748*a(n-17) +100523161525342639*a(n-18) -390340855048743361*a(n-19) +233817541582646426*a(n-20) +2657045726509285686*a(n-21) -2826074288477380324*a(n-22) -10042267477638045785*a(n-23) -893399234003894819*a(n-24) +21271266621127182723*a(n-25) +29807155260119262672*a(n-26) -4592555879996432954*a(n-27) -46721024398304244746*a(n-28) -22705965854461622084*a(n-29) +49126201387464330532*a(n-30) +68141813936973463424*a(n-31) +31547751481543057692*a(n-32) +3384275076564111348*a(n-33) -931910606918155028*a(n-34) +212617089869580916*a(n-35) +118425972661438288*a(n-36) +3200357881449152*a(n-37) +870950365213440*a(n-38) +4393637366976*a(n-39) for n>41.

Example

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

Crossrefs

Cf. A230614.

Sequence in context: A209015 A299951 A230273 * A216592 A202634 A270255

Adjacent sequences: A230610 A230611 A230612 * A230614 A230615 A230616

Keyword

nonn

Author

R. H. Hardin, Oct 25 2013

Status

approved