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A223563 Number of n X n 0..1 arrays with antidiagonals unimodal 1
2, 16, 448, 34496, 6071296, 2137096192, 1363467370496, 1463000488542208, 2490026831498838016, 6414309117941006729216, 24066487810514657248018432, 127383919981054080813761560576, 925826330422301059354419022266368 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Diagonal of A223569

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..99

FORMULA

a(n) = product{ (1+(i*(i+1)/2))^2 , i=1..(n-1) } * (1+(n*(n+1)/2))

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A012678 A012146 A113109 * A140309 A201383 A306816

Adjacent sequences:  A223560 A223561 A223562 * A223564 A223565 A223566

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 22 2013

STATUS

approved

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Last modified December 5 03:03 EST 2021. Contains 349530 sequences. (Running on oeis4.)