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A223680 T(n,k)=Number of nXk 0..1 arrays with rows and antidiagonals unimodal 11

%I #4 Mar 25 2013 11:10:27

%S 2,4,4,7,16,8,11,49,64,16,16,121,316,256,32,22,256,1118,2032,1024,64,

%T 29,484,3177,9822,13045,4096,128,37,841,7745,35509,85663,83737,16384,

%U 256,46,1369,16857,105995,384009,744272,537496,65536,512,56,2116,33615,275775

%N T(n,k)=Number of nXk 0..1 arrays with rows and antidiagonals unimodal

%C Table starts

%C ....2.......4.........7.........11..........16...........22............29

%C ....4......16........49........121.........256..........484...........841

%C ....8......64.......316.......1118........3177.........7745.........16857

%C ...16.....256......2032.......9822.......35509.......105995........275775

%C ...32....1024.....13045......85663......384009......1363639.......4123210

%C ...64....4096.....83737.....744272.....4106403.....17068664......58944337

%C ..128...16384....537496....6458585....43632367....210660192.....821284360

%C ..256...65536...3450100...56030742...462307835...2577807779...11265254628

%C ..512..262144..22145617..486038270..4893189359..31402790284..152970187735

%C .1024.1048576.142149013.4215998078.51766786082.381690187059.2064772010660

%H R. H. Hardin, <a href="/A223680/b223680.txt">Table of n, a(n) for n = 1..480</a>

%F Empirical for column k:

%F k=1: a(n) = 2*a(n-1)

%F k=2: a(n) = 4*a(n-1)

%F k=3: a(n) = 7*a(n-1) -3*a(n-2) -5*a(n-3) +2*a(n-4)

%F k=4: [order 9]

%F k=5: [order 19]

%F k=6: [order 36]

%F k=7: [order 70]

%F Empirical for row n:

%F n=1: a(n) = (1/2)*n^2 + (1/2)*n + 1

%F n=2: a(n) = (1/4)*n^4 + (1/2)*n^3 + (5/4)*n^2 + 1*n + 1

%F n=3: a(n) = (23/360)*n^6 + (31/120)*n^5 + (17/9)*n^4 + (23/24)*n^3 + (917/360)*n^2 + (77/60)*n + 1

%F n=4: polynomial of degree 8

%F n=5: polynomial of degree 10 for n>2

%F n=6: polynomial of degree 12 for n>3

%F n=7: polynomial of degree 14 for n>4

%e Some solutions for n=3 k=4

%e ..0..0..0..0....0..0..1..1....1..1..0..0....0..0..0..1....0..0..0..0

%e ..1..0..0..0....0..1..1..0....0..1..1..0....1..1..0..0....1..0..0..0

%e ..0..0..0..0....0..0..0..1....0..0..0..1....0..0..0..0....1..1..0..0

%Y Column 1 is A000079

%Y Column 2 is A000302

%Y Column 3 is A188868

%Y Row 1 is A000124

%Y Row 2 is A086601

%K nonn,tabl

%O 1,1

%A _R. H. Hardin_ Mar 25 2013

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Last modified July 28 20:51 EDT 2024. Contains 374726 sequences. (Running on oeis4.)