login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A250693 Number of (2+1)X(n+1) 0..3 arrays with nondecreasing x(i,j)-x(i,j-1) in the i direction and nondecreasing absolute value of x(i,j)-x(i-1,j) in the j direction 2
520, 2920, 13906, 60508, 249512, 995624, 3894542, 15061244, 57914756, 222291368, 853854042, 3287692860, 12701872800, 49262782920, 191821043814, 749801489244, 2941369935292, 11575782602248, 45685412767666, 180742482085084 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 2 of A250691

LINKS

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

FORMULA

Empirical: a(n) = 20*a(n-1) -175*a(n-2) +882*a(n-3) -2835*a(n-4) +6072*a(n-5) -8777*a(n-6) +8458*a(n-7) -5204*a(n-8) +1848*a(n-9) -288*a(n-10)

EXAMPLE

Some solutions for n=4

..2..3..1..1..1....0..2..1..0..0....0..1..1..1..2....0..0..3..1..2

..1..2..0..0..0....0..2..2..2..2....0..1..1..1..3....0..0..3..1..2

..0..3..3..3..3....0..3..3..3..3....0..1..1..1..3....0..0..3..1..3

CROSSREFS

Sequence in context: A147854 A147856 A094903 * A200427 A250678 A178269

Adjacent sequences:  A250690 A250691 A250692 * A250694 A250695 A250696

KEYWORD

nonn

AUTHOR

R. H. Hardin, Nov 26 2014

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 30 14:39 EDT 2020. Contains 334725 sequences. (Running on oeis4.)