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A223671 Number of 4Xn 0..1 arrays with rows, diagonals and antidiagonals unimodal 1
16, 256, 1723, 6454, 18980, 49561, 119150, 267643, 567197, 1142224, 2198273, 4062420, 7238132, 12477929, 20877528, 33995513, 54002935, 83867606, 127578211, 190413722, 279263958, 403007495, 572953490, 803354343, 1111996481, 1520876908 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 4 of A223669

LINKS

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

FORMULA

Empirical: a(n) = (1/112)*n^8 - (19/210)*n^7 + (59/45)*n^6 - (61/120)*n^5 - (8789/144)*n^4 + (99083/120)*n^3 - (10598579/2520)*n^2 + (1548737/140)*n - 11539 for n>6

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A189266 A208366 A207714 * A189619 A189691 A188742

Adjacent sequences:  A223668 A223669 A223670 * A223672 A223673 A223674

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 25 2013

STATUS

approved

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Last modified May 27 11:19 EDT 2022. Contains 354096 sequences. (Running on oeis4.)