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!)
A236491 Number of (2+1)X(n+1) 0..2 arrays with the difference between each 2X2 subblock maximum and minimum lexicographically nondecreasing columnwise and nonincreasing rowwise 1

%I #4 Jan 27 2014 04:37:25

%S 583,9839,156087,2339313,34149421,489696691,6952708569,98111759309,

%T 1379571183553,19357628896563,271287317021009,3799259763055641,

%U 53185320056350705,744360921433456291,10416408405407546263

%N Number of (2+1)X(n+1) 0..2 arrays with the difference between each 2X2 subblock maximum and minimum lexicographically nondecreasing columnwise and nonincreasing rowwise

%C Row 2 of A236490

%H R. H. Hardin, <a href="/A236491/b236491.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 26*a(n-1) -112*a(n-2) -1715*a(n-3) +11594*a(n-4) +50442*a(n-5) -400232*a(n-6) -874284*a(n-7) +7189922*a(n-8) +9011756*a(n-9) -78274368*a(n-10) -51795422*a(n-11) +552465656*a(n-12) +120595776*a(n-13) -2596861844*a(n-14) +326924536*a(n-15) +8183202175*a(n-16) -3189752134*a(n-17) -17284950088*a(n-18) +10235206809*a(n-19) +24454223558*a(n-20) -18527589410*a(n-21) -22947355964*a(n-22) +20982286124*a(n-23) +13811550904*a(n-24) -15262048328*a(n-25) -4856880496*a(n-26) +7034342560*a(n-27) +699317696*a(n-28) -1944381056*a(n-29) +96473344*a(n-30) +283617792*a(n-31) -43029504*a(n-32) -15593472*a(n-33) +3317760*a(n-34)

%e Some solutions for n=3

%e ..0..1..2..1....0..2..0..1....1..0..1..2....1..2..0..2....0..0..0..1

%e ..0..0..0..2....0..0..1..2....0..0..1..1....1..1..1..2....1..2..2..2

%e ..0..1..1..0....0..1..2..0....0..0..0..0....0..1..0..2....1..0..0..0

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 27 2014

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified February 20 17:43 EST 2024. Contains 370215 sequences. (Running on oeis4.)