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

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 56th year, we are closing in on 350,000 sequences, and we’ve crossed 9,700 citations (which often say “discovered thanks to the OEIS”).

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A269639 Number of length-n 0..7 arrays with no repeated value differing from the previous repeated value by other than plus two or minus 1. 1
8, 64, 504, 3933, 30444, 234080, 1789528, 13613507, 103118640, 778158768, 5852649288, 43888314093, 328240366020, 2449045039552, 18233174801384, 135479775215950, 1004866303875264, 7440970750295140, 55016954785772120 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 7 of A269640.

LINKS

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

FORMULA

Empirical: a(n) = 56*a(n-1) -1344*a(n-2) +17752*a(n-3) -135716*a(n-4) +545496*a(n-5) -463786*a(n-6) -4675564*a(n-7) +12243456*a(n-8) +21822328*a(n-9) -72836660*a(n-10) -123804240*a(n-11) +151424498*a(n-12) +520495760*a(n-13) +515921322*a(n-14) +232811740*a(n-15) +41061559*a(n-16)

EXAMPLE

Some solutions for n=5

..1. .7. .0. .1. .0. .1. .7. .3. .2. .3. .6. .1. .6. .3. .1. .3

..5. .1. .3. .7. .7. .0. .6. .1. .0. .5. .5. .0. .4. .0. .0. .0

..7. .2. .7. .0. .4. .0. .7. .2. .6. .2. .3. .2. .2. .3. .5. .0

..5. .6. .6. .2. .5. .1. .3. .2. .3. .5. .5. .6. .3. .6. .2. .5

..1. .2. .4. .3. .4. .4. .6. .5. .5. .3. .2. .4. .4. .6. .5. .7

CROSSREFS

Cf. A269640.

Sequence in context: A267470 A227591 A268943 * A269536 A269677 A269408

Adjacent sequences:  A269636 A269637 A269638 * A269640 A269641 A269642

KEYWORD

nonn

AUTHOR

R. H. Hardin, Mar 02 2016

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 December 5 12:24 EST 2021. Contains 349557 sequences. (Running on oeis4.)