A202033 T(n,k)=Number of nXk zero-sum -1..1 arrays with rows and columns lexicographically nondecreasing

1, 2, 2, 2, 7, 2, 3, 21, 21, 3, 3, 56, 181, 56, 3, 4, 130, 1341, 1341, 130, 4, 4, 281, 8312, 29363, 8312, 281, 4, 5, 555, 44300, 537572, 537572, 44300, 555, 5, 5, 1034, 207562, 8249505, 29859761, 8249505, 207562, 1034, 5, 6, 1827, 872998, 108479344

Offset

1,2

Comments

Table starts

.1....2........2............3................3..................4

.2....7.......21...........56..............130................281

.2...21......181.........1341.............8312..............44300

.3...56.....1341........29363...........537572............8249505

.3..130.....8312.......537572.........29859761.........1387552127

.4..281....44300......8249505.......1387552127.......197324899476

.4..555...207562....108479344......54711391946.....23770010642604

.5.1034...872998...1248911674....1867753201968...2467219447235558

.5.1827..3348194..12812139620...56202066220732.224555987749683857

.6.3090.11857834.118772002152.1512619583145180

Links

R. H. Hardin, Table of n, a(n) for n = 1..112

Example

Some solutions for n=2 k=7
.-1..0..0..0..0..1..1...-1.-1.-1..0..1..1..1...-1.-1..0..0..0..0..1
..0.-1.-1.-1..0..1..1....0..0..1..0.-1..0..0....0..1.-1..0..0..0..1

Crossrefs

Sequence in context: A021453 A053789 A115596 * A340742 A029610 A279967

Adjacent sequences: A202030 A202031 A202032 * A202034 A202035 A202036

Keyword

nonn,tabl

Author

R. H. Hardin Dec 09 2011

Status

approved