cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A185477 T(n,k)=Number of (n+2)X(k+2) 0..2 arrays with each 3X3 subblock having rows and columns in lexicographically nondecreasing order.

Original entry on oeis.org

1169, 4594, 4594, 13659, 21834, 13659, 34779, 76309, 76309, 34779, 79743, 225672, 308692, 225672, 79743, 169052, 594798, 1043186, 1043186, 594798, 169052, 336690, 1433903, 3097348, 3959167, 3097348, 1433903, 336690, 636698, 3212372, 8297059
Offset: 1

Views

Author

R. H. Hardin, General degree formula intuited by D. S. McNeil in the Sequence Fans Mailing List, Jan 28 2011

Keywords

Comments

Table starts
....1169.....4594.....13659......34779......79743......169052.......336690
....4594....21834.....76309.....225672.....594798.....1433903......3212372
...13659....76309....308692....1043186....3097348.....8297059.....20411234
...34779...225672...1043186....3959167...12990375....37961900....100908633
...79743...594798...3097348...12990375...46410729...146203201....416227164
..169052..1433903...8297059...37961900..146203201...493061605...1497314456
..336690..3212372..20411234..100908633..416227164..1497314456...4845252741
..636698..6763143..46732687..247920339.1090826214..4179700035..14425457557
.1151966.13496424.100636591..570069808.2669230399.10893560939..40183952539
.2005704.25706057.205574323.1239033996.6166331968.26828743607.106069534256

Examples

			Some solutions for 5X4
..0..0..0..0....0..0..1..1....0..0..0..1....0..0..0..2....0..0..0..1
..0..0..0..2....1..1..1..2....0..0..0..1....1..1..1..2....0..0..1..2
..0..0..1..2....1..1..1..2....0..0..0..1....1..1..1..2....0..1..2..2
..0..1..1..2....1..1..2..1....1..1..2..1....1..1..1..2....0..2..0..0
..2..1..1..2....1..2..0..2....2..2..1..0....1..1..2..2....0..2..2..2
		

Formula

Empirical: T(n,k) is a polynomial of degree 2k+7 in n, for fixed k.
Let T(n,k,z) be the number of (n+2)X(k+2) 0..z arrays with each 3X3 subblock having rows and columns in lexicographically nondecreasing order.
Then empirically T(n,k,z) is a polynomial of degree z*k + z*(z+1)*(z+5)/6 in n, for fixed k.