login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A297224 T(n,k)=Number of nXk 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 1 neighboring 1s. 12

%I #4 Dec 27 2017 15:38:02

%S 1,2,1,3,4,1,4,8,9,1,6,16,24,19,1,9,33,57,68,41,1,13,69,182,207,196,

%T 88,1,19,145,535,997,751,564,189,1,28,300,1513,4210,5570,2720,1620,

%U 406,1,41,624,4415,16658,33158,30946,9861,4660,872,1,60,1300,12832,68769,178469

%N T(n,k)=Number of nXk 0..1 arrays with every 1 horizontally or antidiagonally adjacent to 1 neighboring 1s.

%C Table starts

%C .1...2.....3......4.......6.........9.........13..........19............28

%C .1...4.....8.....16......33........69........145.........300...........624

%C .1...9....24.....57.....182.......535.......1513........4415.........12832

%C .1..19....68....207.....997......4210......16658.......68769........284867

%C .1..41...196....751....5570.....33158.....178469.....1051514.......6152761

%C .1..88...564...2720...30946....261939....1918732....16176806.....134671502

%C .1.189..1620...9861..171851...2063378...20599895...248421807....2936448567

%C .1.406..4660..35741..955316..16277793..221333623..3819208252...64142817874

%C .1.872.13396.129540.5308160.128351805.2377449633.58680928294.1400212345305

%H R. H. Hardin, <a href="/A297224/b297224.txt">Table of n, a(n) for n = 1..611</a>

%F Empirical for column k:

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

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

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

%F k=4: a(n) = a(n-1) +6*a(n-2) +11*a(n-3) +6*a(n-4) +a(n-5)

%F k=5: [order 9]

%F k=6: [order 11] for n>13

%F k=7: [order 16] for n>21

%F Empirical for row n:

%F n=1: a(n) = a(n-1) +a(n-3)

%F n=2: a(n) = a(n-1) +a(n-2) +2*a(n-3) +a(n-4) +a(n-5) -a(n-6)

%F n=3: [order 13]

%F n=4: [order 27]

%F n=5: [order 60]

%e Some solutions for n=5 k=4

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

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

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

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

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

%Y Column 2 is A078039.

%Y Row 1 is A000930(n+1).

%Y Row 2 is A264166.

%K nonn,tabl

%O 1,2

%A _R. H. Hardin_, Dec 27 2017

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 25 11:39 EDT 2024. Contains 371969 sequences. (Running on oeis4.)