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A223665 Number of nX4 0..1 arrays with rows, diagonals and antidiagonals unimodal 1
11, 121, 948, 6454, 44693, 321163, 2343189, 17087771, 124218846, 901767902, 6546694983, 47541956223, 345294309121, 2507850941319, 18213891195978, 132281285512572, 960713718887517, 6977351377339193, 50674293382202763 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A223669

LINKS

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

FORMULA

Empirical: a(n) = 9*a(n-1) -8*a(n-2) -63*a(n-3) +250*a(n-4) -152*a(n-5) -522*a(n-6) -2735*a(n-7) +4120*a(n-8) +9651*a(n-9) +1347*a(n-10) -13682*a(n-11) -24899*a(n-12) +6443*a(n-13) +11258*a(n-14) +8578*a(n-15) -11567*a(n-16) +8480*a(n-17) +22660*a(n-18) -17587*a(n-19) +2236*a(n-20) +4536*a(n-21) -2700*a(n-22) -864*a(n-23)

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A223640 A223633 A223616 * A068179 A293891 A218262

Adjacent sequences:  A223662 A223663 A223664 * A223666 A223667 A223668

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 25 2013

STATUS

approved

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Last modified May 25 19:19 EDT 2022. Contains 354071 sequences. (Running on oeis4.)