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.

27, 729, 13824, 250047, 4019679, 61162984, 876467493, 12040481088, 159131975059, 2037756289752, 25373307641625, 308367729216000, 3667582185888375, 42790530532833000, 490685528946353021, 5539482984199419072

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