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.

A232589 T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with every element next to itself plus and minus one within the range 0..2 horizontally or antidiagonally, with no adjacent elements equal.

Original entry on oeis.org

0, 10, 2, 2, 34, 4, 26, 12, 124, 6, 20, 152, 42, 456, 10, 70, 108, 996, 122, 1686, 18, 90, 690, 606, 6406, 332, 6232, 32, 210, 744, 8104, 3002, 41328, 882, 23034, 56, 336, 3232, 7568, 93236, 14398, 266490, 2322, 85130, 98, 674, 4516, 66744, 68072, 1079300
Offset: 1

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Author

R. H. Hardin, Nov 26 2013

Keywords

Comments

Table starts
...0......10.....2........26.......20...........70..........90.............210
...2......34....12.......152......108..........690.........744............3232
...4.....124....42.......996......606.........8104........7568...........66744
...6.....456...122......6406.....3002........93236.......68072.........1364998
..10....1686...332.....41328....14398......1079300......595304........28339640
..18....6232...882....266490....66950.....12486510.....5045772.......589476500
..32...23034..2322...1718514...306022....144506106....41969054.....12273587770
..56...85130..6092..11082034..1382638...1672314806...344123498....255585490674
..98..314626.15962..71463916..6200520..19353375198..2791211292...5322596390316
.172.1162804.41802.460844060.27671244.223972627480.22459482618.110844512072980

Examples

			Some solutions for n=5 k=4
..2..1..2..1..0....2..1..2..1..0....2..1..0..1..2....0..1..2..1..0
..0..1..2..1..0....0..1..0..1..2....2..1..0..1..2....2..1..0..1..2
..2..1..2..1..2....0..1..2..1..2....0..1..2..1..0....0..1..2..1..2
..0..1..2..1..0....0..1..0..1..2....2..1..0..1..2....0..1..0..1..0
..2..1..2..1..2....0..1..0..1..0....0..1..0..1..0....0..1..2..1..2
..0..1..0..1..0....2..1..2..1..2....2..1..2..1..0....2..1..0..1..0
		

Formula

Empirical for column k:
k=1: a(n) = 2*a(n-1) -a(n-2) +a(n-3)
k=2: a(n) = 4*a(n-1) -a(n-2) -a(n-3) +2*a(n-4)
k=3: a(n) = 4*a(n-1) -4*a(n-2) +a(n-3)
k=4: a(n) = 5*a(n-1) +9*a(n-2) +2*a(n-3) +a(n-4) +2*a(n-5)
k=5: [order 14]
k=6: [order 23] for n>27
k=7: [order 44] for n>45
Empirical for row n:
n=1: a(n) = -a(n-1) +2*a(n-2) +4*a(n-3) +3*a(n-4) +a(n-5)
n=2: [order 9] for n>10
n=3: [order 24] for n>26
n=4: [order 49] for n>54