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A223620 T(n,k)=Number of nXk 0..1 arrays with rows and columns unimodal 7
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 (list; table; graph; refs; listen; history; text; internal format)
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

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Last modified January 27 02:46 EST 2020. Contains 331291 sequences. (Running on oeis4.)