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!)
A224035 Number of n X 5 0..1 arrays with antidiagonals unimodal and rows and diagonals nondecreasing. 1

%I #8 Aug 26 2018 09:50:36

%S 6,26,85,252,734,2149,6321,18673,55373,164729,491332,1468446,4395388,

%T 13170815,39497285,118511408,355728667,1068051097,3207330581,

%U 9632722080,28932821313,86907496260,261060029437,784214341324,2355790958452

%N Number of n X 5 0..1 arrays with antidiagonals unimodal and rows and diagonals nondecreasing.

%C Column 5 of A224038.

%H R. H. Hardin, <a href="/A224035/b224035.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 6*a(n-1) - 10*a(n-2) + a(n-3) + 6*a(n-4) + a(n-5) - 4*a(n-6) + 4*a(n-7) - 4*a(n-8) + 8*a(n-9) for n>10.

%F Empirical g.f.: x*(6 - 10*x - 11*x^2 - 4*x^3 + 10*x^4 + 18*x^5 + 3*x^6 - 14*x^7 - 4*x^9) / ((1 - 2*x)*(1 - 4*x + 2*x^2 + 3*x^3 - x^5 + 2*x^6 + 4*x^8)). - _Colin Barker_, Aug 26 2018

%e Some solutions for n=3:

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

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

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

%Y Cf. A224038.

%K nonn

%O 1,1

%A _R. H. Hardin_, Mar 30 2013

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 30 04:13 EDT 2024. Contains 372118 sequences. (Running on oeis4.)