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!)
A224132 Number of n X 7 0..1 arrays with rows nondecreasing and antidiagonals unimodal. 1
8, 64, 392, 2032, 9577, 42832, 186348, 799954, 3414588, 14548514, 61977436, 264133792, 1126197832, 4803498552, 20492542548, 87435004952, 373077010784, 1591916502840, 6792720587088, 28984532218344, 123676557316928 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A224133.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = 8*a(n-1) - 20*a(n-2) + 18*a(n-3) - 4*a(n-4) + 2*a(n-5) + 8*a(n-6) + 32*a(n-7).

Empirical g.f.: x*(8 + 40*x^2 + 32*x^3 + 41*x^4 + 40*x^5 + 32*x^6) / (1 - 8*x + 20*x^2 - 18*x^3 + 4*x^4 - 2*x^5 - 8*x^6 - 32*x^7). - Colin Barker, Aug 27 2018

EXAMPLE

Some solutions for n=3:

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

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

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

CROSSREFS

Cf. A224133.

Sequence in context: A228460 A202909 A203437 * A297376 A293888 A218267

Adjacent sequences:  A224129 A224130 A224131 * A224133 A224134 A224135

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 31 2013

STATUS

approved

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 May 20 23:05 EDT 2022. Contains 353886 sequences. (Running on oeis4.)