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A183536
Number of nX2 0..3 arrays with each element equal to either the sum mod 4 of its horizontal and vertical neighbors or the sum mod 4 of its diagonal and antidiagonal neighbors
1
4, 16, 43, 128, 416, 1287, 3996, 12594, 39539, 123964, 390822, 1231115, 3878694, 12237024, 38612549, 121853840, 384703976, 1214725443, 3835937346, 12115116500, 38266545975, 120874923256, 381838415718, 1206261483091, 3810809904904
OFFSET
1,1
COMMENTS
Column 2 of A183541
LINKS
FORMULA
Empirical: a(n)=5*a(n-1)+3*a(n-2)-20*a(n-3)-88*a(n-4)+56*a(n-5)+531*a(n-6)+530*a(n-7)-1530*a(n-8)-4123*a(n-9)-750*a(n-10)+11451*a(n-11)+16890*a(n-12)-4861*a(n-13)-43240*a(n-14)-44432*a(n-15)+29396*a(n-16)+103950*a(n-17)+51683*a(n-18)-96473*a(n-19)-119394*a(n-20)+100330*a(n-21)+204492*a(n-22)-168766*a(n-23)-472266*a(n-24)-101730*a(n-25)+570963*a(n-26)+696382*a(n-27)-155331*a(n-28)-761225*a(n-29)-41580*a(n-30)+512100*a(n-31)+204792*a(n-32)-428106*a(n-33)-775382*a(n-34)+71500*a(n-35)+787132*a(n-36)+59480*a(n-37)-388992*a(n-38)-61056*a(n-39)+165888*a(n-40)
EXAMPLE
Some solutions for 3X2
..1..3....0..0....0..0....2..0....0..0....3..3....3..2....2..0....0..2....2..3
..2..2....2..0....1..0....2..2....0..3....0..0....1..3....2..2....2..1....3..1
..1..3....0..2....0..1....2..0....3..0....1..1....0..3....0..2....1..2....3..0
CROSSREFS
Sequence in context: A190090 A227012 A034131 * A320100 A161142 A259013
KEYWORD
nonn
AUTHOR
R. H. Hardin Jan 05 2011
STATUS
approved