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A184371
1/3 the number of (n+1) X 5 0..2 arrays with every 2 X 2 subblock having at least two equal elements connected horizontally or vertically.
1
8019, 880781, 95528423, 10378244309, 1127256514575, 122443114867993, 13299774554091575, 1444622701339019869, 156915034606615850427, 17044123945719790186817, 1851334139596041020316331
OFFSET
1,1
COMMENTS
Column 4 of A184376.
LINKS
FORMULA
Empirical: a(n)=114*a(n-1)-197*a(n-2)-44924*a(n-3)+280944*a(n-4)+3429792*a(n-5)-38126443*a(n-6)+98209829*a(n-7)+162477726*a(n-8)-1059045499*a(n-9)+651177189*a(n-10)+3269771125*a(n-11)-4412158618*a(n-12)-3526224683*a(n-13)+7595898885*a(n-14)+727564626*a(n-15)-4875456557*a(n-16)+367654226*a(n-17)+1090025544*a(n-18)-17907882*a(n-19)-56592728*a(n-20)+3381324*a(n-21)+616392*a(n-22)-47520*a(n-23).
EXAMPLE
Some solutions for 3 X 5 with a(1,1)=0
..0..0..0..1..0....0..0..0..1..1....0..0..0..0..0....0..0..0..0..0
..1..2..2..2..0....0..0..2..2..1....0..1..0..1..1....2..2..0..1..2
..1..1..1..1..1....2..1..1..0..0....2..1..0..0..0....0..2..0..1..0
CROSSREFS
Cf. A184376.
Sequence in context: A345582 A345839 A140929 * A157663 A232075 A109486
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 12 2011
STATUS
approved