A226398 T(n,k)=Number of nondecreasing -k..k vectors of length n whose dot product with some nonincreasing -k..k vector equals n

2, 2, 2, 2, 12, 2, 2, 20, 12, 2, 2, 32, 68, 48, 2, 2, 48, 120, 146, 38, 2, 2, 64, 224, 448, 258, 128, 2, 2, 88, 344, 912, 874, 756, 92, 2, 2, 112, 552, 1646, 2674, 2498, 1012, 282, 2, 2, 136, 752, 2812, 5272, 6900, 4280, 1866, 182, 2, 2, 168, 1100, 4564, 10554, 17812

Offset

1,1

Links

R. H. Hardin, Table of n, a(n) for n = 1..97

Example

Table starts
.2...2....2.....2.....2......2......2.....2......2.....2.....2....2...2.2
.2..12...20....32....48.....64.....88...112....136...168...208..232.280
.2..12...68...120...224....344....552...752...1100..1398..1904.2356
.2..48..146...448...912...1646...2812..4564...6826..9996.14208
.2..38..258...874..2674...5272..10554.18170..30814.48204
.2.128..756..2498..6900..17812..37358.72000.130722
.2..92.1012..4280.15614..41428.109062
.2.282.1866.10992.37804.112060
.2.182.3762.18566.74606
.2.540.5020.32056
Some solutions for n=3 k=4
.-3....1...-4...-3...-1...-4....3...-3...-4...-1...-3...-4...-3...-1....2...-2
..0....3...-1...-3....2...-1....3....1...-3....1...-3...-1...-1....1....3....1
..2....4....1....0....3....0....3....4....2....3....2....3....0....4....3....4

Crossrefs

Sequence in context: A147822 A316497 A084961 * A248768 A334509 A029643

Adjacent sequences: A226395 A226396 A226397 * A226399 A226400 A226401

Keyword

nonn,tabl

Author

R. H. Hardin, Jun 06 2013

Status

approved