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A227676
Number of nX3 0,1 arrays indicating 2X2 subblocks of some larger (n+1)X4 binary array having an odd sum, with rows and columns of the latter in lexicographically nondecreasing order
1
7, 50, 283, 1343, 5434, 19188, 60484, 173433, 459198, 1135975, 2650373, 5876032, 12455509, 25370717, 49868689, 94927157, 175523369, 316075856, 555569995, 955063241, 1608505660, 2658118770, 4315965894, 6893838077, 10844191896
OFFSET
1,1
COMMENTS
Column 3 of A227679
LINKS
FORMULA
Empirical: a(n) = (1/87178291200)*n^14 + (1/958003200)*n^13 + (43/958003200)*n^12 + (1109/958003200)*n^11 + (71/3483648)*n^10 + (7571/29030400)*n^9 + (1530253/609638400)*n^8 + (1146517/87091200)*n^7 + (2010823/21772800)*n^6 + (85537/680400)*n^5 + (66387593/59875200)*n^4 - (218177/19958400)*n^3 + (725933107/151351200)*n^2 - (1777/13860)*n + 1
EXAMPLE
Some solutions for n=4
..0..0..0....0..1..0....0..1..0....0..1..0....0..0..1....0..1..0....1..0..0
..0..0..1....1..1..0....1..0..1....1..0..0....0..1..1....0..0..0....1..0..0
..1..0..1....0..0..0....0..1..1....0..1..1....0..1..1....1..1..0....0..0..0
..0..1..0....1..1..1....0..1..0....1..0..0....0..0..0....1..1..0....0..1..0
CROSSREFS
Sequence in context: A153693 A293475 A293801 * A278875 A266360 A288787
KEYWORD
nonn
AUTHOR
R. H. Hardin Jul 19 2013
STATUS
approved