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.

A212829 T(n,k)=Number of 0..k arrays of length n with no adjacent pair equal to its immediately preceding adjacent pair, and new values introduced in 0..k order.

Original entry on oeis.org

1, 1, 2, 1, 2, 4, 1, 2, 5, 6, 1, 2, 5, 12, 10, 1, 2, 5, 13, 33, 16, 1, 2, 5, 13, 43, 90, 26, 1, 2, 5, 13, 44, 152, 246, 42, 1, 2, 5, 13, 44, 167, 559, 672, 68, 1, 2, 5, 13, 44, 168, 695, 2091, 1836, 110, 1, 2, 5, 13, 44, 168, 716, 3070, 7882, 5016, 178, 1, 2, 5, 13, 44, 168, 717
Offset: 1

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Author

R. H. Hardin May 28 2012

Keywords

Comments

Table starts
...1.....1......1.......1.......1.......1.......1.......1.......1.......1
...2.....2......2.......2.......2.......2.......2.......2.......2.......2
...4.....5......5.......5.......5.......5.......5.......5.......5.......5
...6....12.....13......13......13......13......13......13......13......13
..10....33.....43......44......44......44......44......44......44......44
..16....90....152.....167.....168.....168.....168.....168.....168.....168
..26...246....559.....695.....716.....717.....717.....717.....717.....717
..42...672...2091....3070....3331....3359....3360....3360....3360....3360
..68..1836...7882...14074...16599...17055...17091...17092...17092...17092
.110..5016..29809...65958...87059...92749...93492...93537...93538...93538
.178.13704.112895..313098..473569..534071..545670..546817..546872..546873
.288.37440.427824.1497216.2641428.3220152.3372738.3394616.3396312.3396378

Examples

			Some solutions for n=8 k=4
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..0....1....1....1....1....1....0....1....1....1....0....1....1....1....1....1
..1....2....2....2....2....1....1....2....2....2....0....2....2....0....2....0
..0....3....3....2....1....0....2....3....1....0....1....3....1....2....3....2
..0....4....3....1....3....2....3....1....0....1....2....0....0....1....4....2
..1....3....2....1....4....0....1....3....3....3....0....2....0....0....0....2
..2....3....1....3....2....1....0....2....3....4....1....2....3....0....0....3
..1....1....4....0....0....2....3....4....1....1....0....2....4....3....4....3
		

Crossrefs

Column 1 is A128588

Formula

Empirical for column k:
k=1: a(n) = a(n-1) +a(n-2) for n>3
k=2: a(n) = 2*a(n-1) +2*a(n-2) for n>5
k=3: a(n) = 4*a(n-1) +a(n-2) -6*a(n-3) -3*a(n-4) for n>7
k=4: a(n) = 7*a(n-1) -7*a(n-2) -20*a(n-3) +10*a(n-4) +24*a(n-5) +8*a(n-6) for n>9
k=5: a(n) = 11*a(n-1) -30*a(n-2) -21*a(n-3) +112*a(n-4) +63*a(n-5) -119*a(n-6) -120*a(n-7) -30*a(n-8) for n>11