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A278671 Number of n X 3 0..1 arrays with rows in nondecreasing lexicographic order and columns in nonincreasing lexicographic order, but with exactly one mistake. 1
4, 33, 158, 579, 1801, 4999, 12727, 30218, 67651, 143936, 292799, 572247, 1078870, 1968906, 3488570, 6016844, 10124758, 16656179, 26836284, 42415243, 65856199, 100578425, 151268585, 224275350, 328105245, 474040554, 676903413, 955993903 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = (1/39916800)*n^11 + (1/907200)*n^10 + (17/725760)*n^9 + (19/60480)*n^8 + (3691/1209600)*n^7 + (1003/43200)*n^6 + (21115/145152)*n^5 + (106243/181440)*n^4 + (1170209/907200)*n^3 + (35051/25200)*n^2 + (7783/13860)*n.

Empirical g.f.: x*(4 - 15*x + 26*x^2 - 19*x^3 + x^4 + 8*x^5 - 5*x^6 + x^7) / (1 - x)^12. - Colin Barker, Feb 10 2019

EXAMPLE

Some solutions for n=4:

..0..0..0. .1..1..0. .1..1..0. .1..1..0. .1..0..0. .1..1..1. .1..0..0

..1..1..1. .1..1..0. .1..1..1. .0..0..0. .1..1..0. .1..1..1. .1..1..0

..0..0..0. .0..0..1. .1..0..1. .1..0..1. .0..1..1. .1..1..1. .0..1..0

..1..1..1. .1..0..1. .1..0..1. .1..1..1. .1..0..1. .1..1..0. .0..1..0

CROSSREFS

Column 3 of A278676.

Sequence in context: A041027 A209034 A095671 * A273676 A013192 A273700

Adjacent sequences:  A278668 A278669 A278670 * A278672 A278673 A278674

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 25 2016

STATUS

approved

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Last modified October 18 08:27 EDT 2021. Contains 348067 sequences. (Running on oeis4.)