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!)
A209551 1/4 the number of (n+1)X7 0..3 arrays with every 2X2 subblock having exactly two distinct clockwise edge differences 1
1909, 90186, 3901194, 174401424, 7751834609, 345350598642, 15380031974285, 685056630399243, 30513075478492148, 1359098254767356166, 60536202458667509812, 2696372582587335783278, 120100441888134027505702 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 6 of A209553

LINKS

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

FORMULA

Empirical: a(n) = 93*a(n-1) -2828*a(n-2) +25792*a(n-3) +371376*a(n-4) -9898959*a(n-5) +50997316*a(n-6) +600219584*a(n-7) -8458938650*a(n-8) +15460753459*a(n-9) +324261513320*a(n-10) -1997445245287*a(n-11) -2888253677269*a(n-12) +61818955362264*a(n-13) -105335609798253*a(n-14) -919549637987857*a(n-15) +3635125259976035*a(n-16) +6249958420274094*a(n-17) -54555499290246451*a(n-18) +11571882298429625*a(n-19) +495953594288336739*a(n-20) -657345762489787062*a(n-21) -2942275874522263687*a(n-22) +6881779713200302370*a(n-23) +11244898913169983370*a(n-24) -42974781730107130109*a(n-25) -23051215421912913536*a(n-26) +185864776798114709968*a(n-27) -12863209686911573111*a(n-28) -587984628431521336548*a(n-29) +276016166528678978015*a(n-30) +1397897524468136739882*a(n-31) -1073664296329817362259*a(n-32) -2537929904791966336740*a(n-33) +2568552806109627886272*a(n-34) +3559706199665273218930*a(n-35) -4354397060651285431293*a(n-36) -3901454743539065189517*a(n-37) +5483143910166447182278*a(n-38) +3391429255331125848034*a(n-39) -5229357377757064837770*a(n-40) -2387498579023401955317*a(n-41) +3802827193424184634130*a(n-42) +1394499277589912306144*a(n-43) -2104672583906607527310*a(n-44) -686223001308051264232*a(n-45) +877657767435453737858*a(n-46) +281766806240431459892*a(n-47) -270362730870675484681*a(n-48) -92957087420024768497*a(n-49) +59494538810619139593*a(n-50) +23369146321510311361*a(n-51) -8826604119797680384*a(n-52) -4236074000925921714*a(n-53) +782901241541277381*a(n-54) +524243697816902673*a(n-55) -26069037492083522*a(n-56) -41764242069671064*a(n-57) -1908566223569902*a(n-58) +1979458374052951*a(n-59) +240266789154528*a(n-60) -47527093603425*a(n-61) -10067754548810*a(n-62) +255750935719*a(n-63) +181717983160*a(n-64) +9192680176*a(n-65) -1053768700*a(n-66) -122161293*a(n-67) -1991984*a(n-68) +258490*a(n-69) +14852*a(n-70) +296*a(n-71) +2*a(n-72)

EXAMPLE

Some solutions for n=4

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

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

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

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

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

CROSSREFS

Sequence in context: A206124 A251463 A184194 * A238059 A186789 A229390

Adjacent sequences:  A209548 A209549 A209550 * A209552 A209553 A209554

KEYWORD

nonn

AUTHOR

R. H. Hardin Mar 10 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
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified January 18 00:30 EST 2022. Contains 350410 sequences. (Running on oeis4.)