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

 

Logo

Please make a donation to keep the OEIS running. We are now in our 56th year. In the past year we added 10000 new sequences and reached almost 9000 citations (which often say "discovered thanks to the OEIS").
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A204345 Number of (n+2)X4 0..3 arrays with no 3X3 subblock having three equal diagonal elements or three equal antidiagonal elements, and new values 0..3 introduced in row major order 1
540324, 109655775, 22275534255, 4524628081600, 919046909794048, 186677705463298720, 37918176847270068655, 7701980533069758424335, 1564434504820385808145956, 317769606176319633834643104 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A204351

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..180

FORMULA

Empirical: a(n) = 217*a(n-1) -2496*a(n-2) -59194*a(n-3) -1263479*a(n-4) -9752889*a(n-5) +8960540*a(n-6) +36108251782*a(n-7) -249908138142*a(n-8) -274708063924*a(n-9) +963469531573*a(n-10) +9614519279043*a(n-11) +19959867347978*a(n-12) +11744804824456*a(n-13) -378612498274341*a(n-14) -703194230351803*a(n-15) -1031730471573992*a(n-16) +373184847863472*a(n-17) +5118782848172432*a(n-18) +29399642640552808*a(n-19) +155979057144003606*a(n-20) +517288794880483746*a(n-21) +509022762066757008*a(n-22) -2538543123728192628*a(n-23) -10628760266216741214*a(n-24) -25069276602228200490*a(n-25) -20041975242938092176*a(n-26) +3995626027775196780*a(n-27) +53476384692194416836*a(n-28) +488407961655493484832*a(n-29) +2126200047857773714602*a(n-30) +4758980325020420047470*a(n-31) +1677161298602998054260*a(n-32) -13158199476451520128080*a(n-33) -63146824595959597077762*a(n-34) -20652418268047942847046*a(n-35) +6044640047603966442600*a(n-36) +45745287981567528373632*a(n-37) +16573763093004275374656*a(n-38) -4644239273776591306920*a(n-39) -44173754942126735105253*a(n-40) -16630897273553099306763*a(n-41) +7182224847804062362752*a(n-42) +65046961496300577485310*a(n-43) +25998213831568118378757*a(n-44) +2356533098526734850195*a(n-45) -8918150363976493791756*a(n-46) -5437020685725553472802*a(n-47) -1951572856621062412278*a(n-48) +252519901744191301332*a(n-49) +297175779354283594353*a(n-50) +147679738208660982879*a(n-51) +18698620834571832882*a(n-52) +222362422662220920*a(n-53) -2151356439256987401*a(n-54) +150094635296999121*a(n-55)

EXAMPLE

Some solutions for n=3

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

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

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

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

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

CROSSREFS

Sequence in context: A251355 A043636 A082813 * A269323 A043667 A126722

Adjacent sequences:  A204342 A204343 A204344 * A204346 A204347 A204348

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 14 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 November 28 06:23 EST 2020. Contains 338699 sequences. (Running on oeis4.)