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A183452
Number of n X 5 binary arrays with every 1 having exactly three king-move neighbors equal to 1.
2
1, 6, 13, 22, 60, 147, 310, 723, 1723, 3917, 8973, 20875, 48427, 111384, 256857, 599340, 1384994, 3187563, 7469888, 17334233, 39905291, 94076289, 219435873, 505824167, 1202595689, 2825927772, 6530389759, 15704159500, 37297212976
OFFSET
1,2
COMMENTS
Column 5 of A183456.
LINKS
FORMULA
Conjecture: g.f. -x*(1 +5*x +607360*x^20 -11532*x^9 +753306*x^19 +6*x^2 -288*x^26 -57080*x^10 -612804*x^16 +7234*x^8 -600857*x^17 +181998*x^18 -57*x^3 -10592*x^25 -16800*x^24 -182104*x^23 -283*x^4 +5942*x^7 -132231*x^15 -345*x^5 +1200*x^6+ 285093*x^14 +259034*x^13 +52803*x^12 +384*x^29 +768*x^28 +2048*x^27 -67623*x^11 -344072*x^22 -99176*x^21)/(-1 +x +275562*x^20 +15867*x^9 -37876*x^19 +x^2 -8768*x^26 +384*x^30 -7896*x^10 -20075*x^16 +1261*x^8 -184239*x^17 -567185*x^18 +60*x^3 -8096*x^25 -174456*x^24 -168944*x^23 -52*x^4+980*x^7 +311194*x^15-58*x^5 -1393*x^6 +65529*x^14 +24304*x^13 -94858*x^12 +384*x^29 +1664*x^28 -1952*x^27 -12862*x^11 +73800*x^22 +537480*x^21) . - R. J. Mathar, Dec 03 2022
EXAMPLE
Some solutions for 7X5
..0..0..0..1..1....0..0..0..1..1....0..0..0..0..0....0..0..0..0..0
..1..1..0..1..1....0..0..0..1..1....0..1..1..0..0....0..0..0..0..0
..1..1..0..0..0....0..0..0..0..0....0..1..1..0..0....1..1..0..0..0
..0..0..0..0..0....0..0..0..0..0....0..0..0..0..0....1..1..0..1..1
..0..0..0..0..0....0..0..0..0..0....1..1..0..0..0....0..0..0..1..1
..1..1..0..1..1....0..0..0..1..1....1..1..0..1..1....1..1..0..0..0
..1..1..0..1..1....0..0..0..1..1....0..0..0..1..1....1..1..0..0..0
CROSSREFS
Sequence in context: A049718 A036707 A054311 * A323423 A236577 A356091
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 05 2011
STATUS
approved