A223620 - OEIS

A223620

T(n,k) = Number of n X k 0..1 arrays with rows and columns unimodal.

2, 4, 4, 7, 16, 7, 11, 49, 49, 11, 16, 121, 240, 121, 16, 22, 256, 876, 876, 256, 22, 29, 484, 2582, 4466, 2582, 484, 29, 37, 841, 6504, 17594, 17594, 6504, 841, 37, 46, 1369, 14547, 57238, 89630, 57238, 14547, 1369, 46, 56, 2116, 29659, 160883, 367216, 367216

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OFFSET

1,1

COMMENTS

Table starts

..2....4......7......11.......16........22.........29..........37..........46

..4...16.....49.....121......256.......484........841........1369........2116

..7...49....240.....876.....2582......6504......14547.......29659.......56161

.11..121....876....4466....17594.....57238.....160883......403159......921181

.16..256...2582...17594....89630....367216....1271969.....3857481....10504174

.22..484...6504...57238...367216...1856100....7795951....28248007....90732638

.29..841..14547..160883..1271969...7795951...39162020...167679972...629671260

.37.1369..29659..403159..3857481..28248007..167679972...840122330..3659134776

.46.2116..56161..921181.10504174..90732638..629671260..3659134776.18350758538

.56.3136.100123.1951247.26169386.263650284.2118764468.14165886974.81249849522

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..363

FORMULA

Empirical: columns k=1..7 are polynomials of degree 2*k.

EXAMPLE

Some solutions for n=4 k=4

..1..0..0..0....1..0..0..0....0..1..0..0....1..0..0..0....1..1..0..0

..0..1..1..1....1..1..0..0....1..1..0..0....1..0..0..0....1..1..0..0

..0..0..1..0....1..0..0..0....1..1..0..0....0..1..1..1....0..0..0..1

..0..0..0..0....0..0..1..1....1..1..1..1....0..0..0..0....0..0..0..0

CROSSREFS

Column 1 is A000124.

Column 2 is A086601.

Sequence in context: A227103 A223644 A223637 * A227679 A223782 A223716

Adjacent sequences: A223617 A223618 A223619 * A223621 A223622 A223623

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Mar 24 2013

STATUS

approved