A223179 T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with all rows and columns having a strictly positive second derivative in a quadratic least squares fit

0, 0, 0, 0, 4, 0, 0, 40, 40, 0, 0, 348, 2076, 348, 0, 0, 1200, 48316, 48316, 1200, 0, 0, 16348, 620568, 2485972, 620568, 16348, 0, 0, 94364, 14777316, 76317552, 76317552, 14777316, 94364, 0, 0, 524292, 246091276, 3171271500, 6269400000, 3171271500

Offset

1,5

Comments

Table starts

.0........0............0..............0................0.................0

.0........4...........40............348.............1200.............16348

.0.......40.........2076..........48316...........620568..........14777316

.0......348........48316........2485972.........76317552........3171271500

.0.....1200.......620568.......76317552.......6269400000......591850045248

.0....16348.....14777316.....3171271500.....591850045248...104799995226404

.0....94364....246091276...115722707546...50320121297406.17691602460630154

.0...524292...3081824360..2886324889628.2512348229420136

.0..2621432..43744483080.88035882884812

.0.16536796.658808677292

.0.84487288

Links

R. H. Hardin, Table of n, a(n) for n = 1..81

Example

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

Crossrefs

Sequence in context: A181204 A191417 A307050 * A278272 A192057 A054376

Adjacent sequences: A223176 A223177 A223178 * A223180 A223181 A223182

Keyword

nonn,tabl

Author

R. H. Hardin, Mar 17 2013

Status

approved