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.

A241054 T(n,k)=Number of nXk 0..3 arrays with no element equal to one plus the sum of elements to its left or zero plus the sum of the elements above it or zero plus the sum of the elements diagonally to its northwest or one plus the sum of the elements antidiagonally to its northeast, modulo 4.

Original entry on oeis.org

2, 3, 2, 4, 3, 4, 7, 2, 4, 6, 10, 10, 3, 6, 8, 15, 18, 24, 6, 8, 14, 24, 18, 60, 64, 6, 12, 20, 35, 46, 93, 163, 132, 15, 13, 30, 54, 58, 297, 280, 598, 690, 31, 20, 48, 83, 102, 507, 1423, 1392, 3411, 2142, 58, 28, 70, 124, 173, 1264, 4167, 10921, 13273, 11283, 7144, 170, 38
Offset: 1

Views

Author

R. H. Hardin, Apr 15 2014

Keywords

Comments

Table starts
..2..3...4.....7......10........15..........24..........35..........54
..2..3...2....10......18........18..........46..........58.........102
..4..4...3....24......60........93.........297.........507........1264
..6..6...6....64.....163.......280........1423........4167.......13389
..8..8...6...132.....598......1392.......10921.......72769......370453
.14.12..15...690....3411.....13273......189680.....2667280....18820225
.20.13..31..2142...11283.....89910.....1511923....30914092...376386754
.30.20..58..7144...72578...1128052....35582068..1432670661.26960360814
.48.28.170.30662..404421..13331118...776191453.62057946683
.70.38.388.95669.2220973.128026529.14877945554

Examples

			Some solutions for n=4 k=4
..3..2..3..3....3..3..2..2....3..2..3..2....3..3..2..3....3..3..2..2
..2..1..1..0....2..1..1..3....2..1..1..0....2..1..1..0....2..1..1..3
..2..0..2..0....3..3..2..2....2..1..3..0....3..3..2..2....3..3..2..3
..2..0..0..0....2..0..2..0....2..1..2..0....3..1..0..0....2..1..2..3
		

Crossrefs

Column 1 is A239851
Row 1 is A159288(n+1)

Formula

Empirical for column k:
k=1: a(n) = a(n-2) +2*a(n-3)
k=2: a(n) = 2*a(n-2) -a(n-4) +a(n-5) -a(n-7) +a(n-8) +a(n-11) for n>15
Empirical for row n:
n=1: a(n) = a(n-2) +2*a(n-3)
n=2: [order 15] for n>17
n=3: [order 70] for n>85