login
This site is supported by donations to The OEIS Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A245158 Number of length n 0..3 arrays with new values introduced in order from both ends 1
1, 1, 2, 4, 9, 23, 65, 199, 653, 2275, 8313, 31439, 121637, 477307, 1888721, 7509799, 29940861, 119550419, 477742889, 1909988479, 7637856725, 30546970411, 122178444417, 488693854679, 1954733475629, 7818845822083, 31275198738905 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Column 3 of A245163

LINKS

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

FORMULA

Empirical: a(n) = 10*a(n-1) -37*a(n-2) +64*a(n-3) -52*a(n-4) +16*a(n-5) for n>6

EXAMPLE

Some solutions for n=7

..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0

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

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

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

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

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

..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0

CROSSREFS

Sequence in context: A092668 A164039 A014137 * A245159 A245160 A245161

Adjacent sequences:  A245155 A245156 A245157 * A245159 A245160 A245161

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jul 12 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 | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified October 19 13:38 EDT 2018. Contains 316361 sequences. (Running on oeis4.)