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A223791 Number of 4Xn 0..2 arrays with rows, diagonals and antidiagonals unimodal 1
81, 6561, 151580, 1560013, 11012718, 61333566, 288823579, 1196519547, 4468789562, 15293854291, 48524120300, 143996244303, 402491787780, 1065874328092, 2687501352957, 6479586585575, 14994608609716, 33416226803133 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 4 of A223789

LINKS

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

FORMULA

Empirical: a(n) = (456419/5230697472000)*n^16 + (165527/653837184000)*n^15 + (1160527/37362124800)*n^14 + (4098907/18681062400)*n^13 - (2323961/28740096000)*n^12 + (686821469/7185024000)*n^11 - (1282316951/1828915200)*n^10 + (6465409549/914457600)*n^9 + (69811138547/5225472000)*n^8 - (199799815457/326592000)*n^7 + (10755338490607/1437004800)*n^6 - (18136370082679/359251200)*n^5 + (23466839810116957/108972864000)*n^4 - (2416825957955693/4540536000)*n^3 + (2240986165151/4324320)*n^2 + (7139372965/18018)*n - 659081 for n>8

EXAMPLE

Some solutions for n=3

..1..1..1....0..1..0....1..1..0....0..1..2....0..2..0....0..0..1....1..2..0

..0..2..0....0..2..0....2..2..2....2..1..0....0..1..1....1..0..0....0..1..1

..2..1..0....0..0..2....0..2..2....1..1..0....0..1..2....0..1..0....1..2..0

..1..1..0....0..1..0....1..2..1....1..2..1....2..2..1....0..2..1....1..1..2

CROSSREFS

Sequence in context: A178513 A016948 A206993 * A206935 A206870 A181223

Adjacent sequences:  A223788 A223789 A223790 * A223792 A223793 A223794

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 27 2013

STATUS

approved

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Last modified February 17 17:12 EST 2019. Contains 320222 sequences. (Running on oeis4.)