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

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A210543 Number of arrays of n nonnegative integers with value i>0 appearing only after i-1 has appeared at least 6 times 1
1, 1, 1, 1, 1, 1, 2, 4, 8, 16, 32, 64, 129, 267, 582, 1364, 3454, 9338, 26429, 76929, 227579, 680113, 2050000, 6242818, 19284165, 60754153, 196341570, 654012814, 2251195713, 8005274899, 29325473071, 110181281435, 422565983725 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,7

COMMENTS

Column 6 of A210545

LINKS

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

FORMULA

a(n) = 1 if n<=6 else sum{i=0..n-6}(binomial(n-6,i)*a(i))

EXAMPLE

Some solutions for n=17

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

CROSSREFS

Sequence in context: A023422 A084638 A157021 * A006211 A180209 A275073

Adjacent sequences:  A210540 A210541 A210542 * A210544 A210545 A210546

KEYWORD

nonn

AUTHOR

R. H. Hardin, formula proved by R. J. Mathar in the Sequence Fans Mailing List, Mar 22 2012

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 February 25 03:06 EST 2018. Contains 299630 sequences. (Running on oeis4.)