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A268022 Number of nX3 0..2 arrays with every repeated value in every row greater than or equal to, and in every column greater than, the previous repeated value. 1
27, 729, 13824, 250047, 4019679, 61162984, 876467493, 12040481088, 159131975059, 2037756289752, 25373307641625, 308367729216000, 3667582185888375, 42790530532833000, 490685528946353021, 5539482984199419072 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A268026.

LINKS

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

FORMULA

Empirical: a(n) = 56*a(n-1) -1170*a(n-2) +8532*a(n-3) +59031*a(n-4) -1349748*a(n-5) +4015908*a(n-6) +64757664*a(n-7) -463647600*a(n-8) -1255566144*a(n-9) +19457594304*a(n-10) -3621049344*a(n-11) -467191259136*a(n-12) +700630695936*a(n-13) +7110421807104*a(n-14) -15956683259904*a(n-15) -70142096572416*a(n-16) +189870895005696*a(n-17) +438443477827584*a(n-18) -1332652586041344*a(n-19) -1652114199674880*a(n-20) +5489741298401280*a(n-21) +3651168878198784*a(n-22) -12532783289204736*a(n-23) -5719659487690752*a(n-24) +15199648742375424*a(n-25) +6966505673588736*a(n-26) -7881299347898368*a(n-27) -4503599627370496*a(n-28)

EXAMPLE

Some solutions for n=3

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

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

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

CROSSREFS

Cf. A268026.

Sequence in context: A223790 A223976 A167726 * A223571 A228973 A171301

Adjacent sequences:  A268019 A268020 A268021 * A268023 A268024 A268025

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 24 2016

STATUS

approved

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Last modified December 7 15:24 EST 2021. Contains 349581 sequences. (Running on oeis4.)