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A223565 Number of nX4 0..1 arrays with antidiagonals unimodal 1
16, 256, 3136, 34496, 379456, 4174016, 45914176, 505055936, 5555615296, 61111768256, 672229450816, 7394523958976, 81339763548736, 894737399036096, 9842111389397056, 108263225283367616, 1190895478117043776 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 4 of A223569

LINKS

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

FORMULA

a(n) = product{ (1+(i*(i+1)/2))^2 , i=1..(min(n,4)-1) } * (1+(min(n,4)*(min(n,4)+1)/2))^(max(n,4)-min(n,4)+1)

a(n) = 11*a(n-1) for n>3

EXAMPLE

Some solutions for n=4

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

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

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

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

CROSSREFS

Sequence in context: A297377 A283860 A223660 * A223677 A207277 A294329

Adjacent sequences:  A223562 A223563 A223564 * A223566 A223567 A223568

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 22 2013

STATUS

approved

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Last modified October 16 07:07 EDT 2021. Contains 348041 sequences. (Running on oeis4.)