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.

A253397 T(n,k)=Number of (n+1)X(k+1) 0..1 arrays with every 2X2 subblock antidiagonal maximum minus diagonal minimum nondecreasing horizontally and diagonal maximum minus antidiagonal minimum nondecreasing vertically.

Original entry on oeis.org

16, 44, 44, 96, 102, 96, 180, 143, 143, 180, 304, 197, 174, 197, 304, 476, 250, 246, 246, 250, 476, 704, 320, 316, 346, 316, 320, 704, 996, 391, 419, 465, 465, 419, 391, 996, 1360, 477, 520, 632, 666, 632, 520, 477, 1360, 1804, 564, 651, 823, 932, 932, 823, 651
Offset: 1

Views

Author

R. H. Hardin, Dec 31 2014

Keywords

Comments

Table starts
...16..44..96..180..304..476..704...996..1360..1804..2336..2964..3696..4540
...44.102.143..197..250..320..391...477...564...666...769...887..1006..1140
...96.143.174..246..316..419..520...651...780...939..1096..1283..1468..1683
..180.197.246..346..465..632..823..1071..1351..1695..2079..2535..3039..3623
..304.250.316..465..666..932.1269..1693..2201..2814..3527..4360..5309..6394
..476.320.419..632..932.1318.1855..2528..3408..4498..5864..7521..9542.11949
..704.391.520..823.1269.1855.2726..3810..5311..7163..9569.12493.16140.20493
..996.477.651.1071.1693.2528.3810..5396..7717.10593.14543.19463.25921.33918
.1360.564.780.1351.2201.3408.5311..7717.11392.15966.22500.30675.41701.55452
.1804.666.939.1695.2814.4498.7163.10593.15966.22634.32533.44959.62402.84560

Examples

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

Crossrefs

Column 1 is A217873(n+1)

Formula

Empirical for column k:
k=1: a(n) = (4/3)*n^3 + 4*n^2 + (20/3)*n + 4
k=2: a(n) = 2*a(n-1) -2*a(n-3) +a(n-4) for n>8
k=3: a(n) = 2*a(n-1) -2*a(n-3) +a(n-4) for n>8
k=4: a(n) = 3*a(n-1) -2*a(n-2) -2*a(n-3) +3*a(n-4) -a(n-5) for n>11
k=5: a(n) = 3*a(n-1) -2*a(n-2) -2*a(n-3) +3*a(n-4) -a(n-5) for n>13
k=6: a(n) = 4*a(n-1) -5*a(n-2) +5*a(n-4) -4*a(n-5) +a(n-6) for n>16
k=7: a(n) = 4*a(n-1) -5*a(n-2) +5*a(n-4) -4*a(n-5) +a(n-6) for n>18
Empirical quasipolynomials for column k:
k=2: polynomial of degree 2 plus a quasipolynomial of degree 0 with period 2 for n>4
k=3: polynomial of degree 2 plus a quasipolynomial of degree 0 with period 2 for n>4
k=4: polynomial of degree 3 plus a quasipolynomial of degree 0 with period 2 for n>6
k=5: polynomial of degree 3 plus a quasipolynomial of degree 0 with period 2 for n>8
k=6: polynomial of degree 4 plus a quasipolynomial of degree 0 with period 2 for n>10
k=7: polynomial of degree 4 plus a quasipolynomial of degree 0 with period 2 for n>12