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A278379
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Number of n X 2 0..1 arrays with rows and columns in lexicographic nondecreasing order but with exactly three mistakes.
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1
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0, 0, 3, 40, 267, 1350, 5936, 23565, 84912, 278422, 835824, 2316601, 5980937, 14503972, 33282396, 72732358, 152195016, 306378420, 595704701, 1122541470, 2056128263, 3670127802, 6398217740, 10915088955, 18252749400, 29965289850
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OFFSET
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1,3
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COMMENTS
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Column 2 of A278385.
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LINKS
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R. H. Hardin, Table of n, a(n) for n = 1..210
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FORMULA
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Empirical: a(n) = (1/1307674368000)*n^15 + (1/12454041600)*n^14 + (149/37362124800)*n^13 + (31/319334400)*n^12 + (1517/1306368000)*n^11 + (169/87091200)*n^10 - (73537/1828915200)*n^9 - (3971/87091200)*n^8 + (2939219/653184000)*n^7 + (521/2419200)*n^6 - (1516673/44906400)*n^5 - (19007/59875200)*n^4 + (351393113/4540536000)*n^3 + (3149/21621600)*n^2 - (5/104)*n.
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EXAMPLE
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Some solutions for n=4
..1..0. .1..0. .1..1. .0..0. .1..1. .1..1. .1..1. .1..0. .1..0. .1..0
..0..1. .0..1. .1..0. .1..1. .1..0. .1..1. .1..0. .0..0. .0..0. .0..1
..0..0. .1..0. .1..1. .1..0. .1..1. .1..0. .0..1. .1..0. .1..1. .0..0
..0..0. .0..1. .0..1. .0..1. .0..0. .0..1. .0..1. .0..1. .0..1. .1..0
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CROSSREFS
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Cf. A278385.
Sequence in context: A013286 A013291 A013292 * A181395 A165395 A165386
Adjacent sequences: A278376 A278377 A278378 * A278380 A278381 A278382
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KEYWORD
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nonn
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AUTHOR
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R. H. Hardin, Nov 20 2016
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STATUS
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approved
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