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.

A245163 T(n,k)=Number of length n 0..k arrays with new values introduced in order from both ends.

Original entry on oeis.org

1, 1, 1, 1, 1, 2, 1, 1, 2, 4, 1, 1, 2, 4, 8, 1, 1, 2, 4, 9, 16, 1, 1, 2, 4, 9, 23, 32, 1, 1, 2, 4, 9, 23, 64, 64, 1, 1, 2, 4, 9, 23, 65, 186, 128, 1, 1, 2, 4, 9, 23, 65, 199, 551, 256, 1, 1, 2, 4, 9, 23, 65, 199, 653, 1645, 512, 1, 1, 2, 4, 9, 23, 65, 199, 654, 2275, 4926, 1024, 1, 1, 2, 4, 9, 23
Offset: 1

Views

Author

R. H. Hardin, Jul 12 2014

Keywords

Comments

Table starts
.....1........1.........1.........1.........1.........1.........1.........1
.....1........1.........1.........1.........1.........1.........1.........1
.....2........2.........2.........2.........2.........2.........2.........2
.....4........4.........4.........4.........4.........4.........4.........4
.....8........9.........9.........9.........9.........9.........9.........9
....16.......23........23........23........23........23........23........23
....32.......64........65........65........65........65........65........65
....64......186.......199.......199.......199.......199.......199.......199
...128......551.......653.......654.......654.......654.......654.......654
...256.....1645......2275......2296......2296......2296......2296......2296
...512.....4926......8313......8568......8569......8569......8569......8569
..1024....14768.....31439.....33794.....33825.....33825.....33825.....33825
..2048....44293....121637....140039....140580....140581....140581....140581
..4096...132867....477307....605869....612890....612933....612933....612933
..8192...398588...1888721...2718531...2794159...2795181...2795182...2795182
.16384..1195750...7509799..12564289..13280627..13298407..13298464..13298464
.32768..3587235..29940861..59419764..65597882..65851100..65852872..65852873
.65536.10761689.119550419.285878342.335521900.338654554.338694406.338694479

Examples

			Some solutions for n=10 k=4
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..1....1....1....1....0....1....0....1....0....1....1....0....0....1....1....0
..1....0....2....0....1....2....1....0....0....2....2....0....1....1....2....1
..0....1....3....1....2....0....0....2....0....2....1....1....0....1....2....0
..1....2....0....0....0....1....2....3....0....3....1....2....1....1....2....1
..0....2....0....2....2....1....0....3....1....1....0....1....2....2....2....0
..0....1....2....1....2....1....0....2....1....3....2....1....1....1....1....2
..0....1....1....2....1....1....1....0....1....2....1....1....1....2....1....1
..1....1....1....1....1....1....0....1....0....1....1....0....1....1....1....1
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
		

Crossrefs

Column 1 is A000079(n-2)
Column 2 is A164039(n-2)
Diagonal is A007476

Formula

Empirical for column k:
k=1: a(n) = 2*a(n-1) for n>2
k=2: a(n) = 5*a(n-1) -7*a(n-2) +3*a(n-3) for n>4
k=3: a(n) = 10*a(n-1) -37*a(n-2) +64*a(n-3) -52*a(n-4) +16*a(n-5) for n>6
k=4: [order 7] for n>8
k=5: [order 9] for n>10
k=6: [order 11] for n>12
k=7: [order 13] for n>14