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.

A229534 T(n,k) = number of defective 3-colorings of an n X k 0..2 array connected horizontally, diagonally and antidiagonally with exactly one mistake, and colors introduced in row-major 0..2 order.

Original entry on oeis.org

0, 1, 0, 2, 4, 0, 6, 8, 20, 0, 16, 36, 58, 84, 0, 40, 112, 361, 356, 324, 0, 96, 368, 1588, 3064, 2038, 1188, 0, 224, 1152, 7460, 19276, 24344, 11184, 4212, 0, 512, 3568, 33136, 130854, 221096, 185808, 59626, 14580, 0, 1152, 10880, 146300, 833108, 2171944
Offset: 1

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Author

R. H. Hardin, Sep 25 2013

Keywords

Comments

Table starts
.0.....1......2........6........16.........40...........96...........224
.0.....4......8.......36.......112........368.........1152..........3568
.0....20.....58......361......1588.......7460........33136........146300
.0....84....356.....3064.....19276.....130854.......833108.......5305746
.0...324...2038....24344....221096....2171944.....19965136.....184319130
.0..1188..11184...185808...2451728...34811238....463976296....6218438820
.0..4212..59626..1379512..26566266..544403948..10551803060..205336122417
.0.14580.311260.10036352.283010776.8359264560.236116939092.6668992563052

Examples

			Some solutions for n=3, k=4:
  0 1 0 1     0 1 0 2     0 1 0 0     0 1 0 0     0 1 2 0
  0 2 0 2     1 2 0 2     0 1 2 1     2 1 2 1     0 1 2 0
  2 1 0 1     1 2 0 2     2 1 2 1     0 1 2 1     2 1 0 1
		

Crossrefs

Column 2 is A167682(n-1).
Row 1 is A057711(n-1).

Formula

Empirical for column k:
k=1: a(n) = a(n-1).
k=2: a(n) = 6*a(n-1) - 9*a(n-2) for n > 3.
k=3: a(n) = 10*a(n-1) - 29*a(n-2) + 20*a(n-3) - 4*a(n-4) for n > 5.
k=4: a(n) = 14*a(n-1) - 57*a(n-2) + 56*a(n-3) - 16*a(n-4) for n > 5.
k=5: [order 12] for n > 13.
k=6: [order 18] for n > 19.
k=7: [order 38] for n > 39.
Empirical for row n:
n=1: a(n) = 4*a(n-1) - 4*a(n-2) for n > 4.
n=2: a(n) = 4*a(n-1) - 8*a(n-3) - 4*a(n-4).
n=3: a(n) = 6*a(n-1) - a(n-2) - 28*a(n-3) - 4*a(n-4) + 16*a(n-5) - 4*a(n-6) for n > 8.
n=4: [order 12] for n > 14.
n=5: [order 20] for n > 22.
n=6: [order 46] for n > 48.
n=7: [order 92] for n > 94.