|
| |
|
|
A197644
|
|
Number of nX4 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 4,2,2,0,2 for x=0,1,2,3,4
|
|
1
|
|
|
|
1, 31, 342, 2910, 25273, 251972, 2579814, 24550379, 230860577, 2228487362, 21701017288, 209232791158, 2007839656980, 19335726884633, 186641182758431, 1799468819059552, 17330304902080402, 166963816148786657
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
|
OFFSET
|
1,2
|
|
|
COMMENTS
|
Every 0 is next to 0 4's, every 1 is next to 1 2's, every 2 is next to 2 2's, every 3 is next to 3 0's, every 4 is next to 4 2's
|
|
|
LINKS
|
|
|
|
FORMULA
|
Empirical: a(n) = 9*a(n-1) -12*a(n-2) +125*a(n-3) +1188*a(n-4) -4683*a(n-5) -20426*a(n-6) +23085*a(n-7) -285475*a(n-8) +51944*a(n-9) +3410113*a(n-10) -1616159*a(n-11) +11659968*a(n-12) +70876989*a(n-13) -287458376*a(n-14) -79618646*a(n-15) +126600327*a(n-16) -457268027*a(n-17) +2660774827*a(n-18) +5224619238*a(n-19) -15669734700*a(n-20) +6771218194*a(n-21) +6121483112*a(n-22) -31180263251*a(n-23) +26942793264*a(n-24) +54371560903*a(n-25) -86658907897*a(n-26) +1609458131*a(n-27) -30362436308*a(n-28) +232978747793*a(n-29) -197086970029*a(n-30) +182277578647*a(n-31) -415970917520*a(n-32) +156986155987*a(n-33) +262241730636*a(n-34) -176381184554*a(n-35) +51972930089*a(n-36) -130169769163*a(n-37) +190494666208*a(n-38) -113932599654*a(n-39) -5323724963*a(n-40) +20288901787*a(n-41) +5998341425*a(n-42) +104384441*a(n-43) -9690118586*a(n-44) +7508363536*a(n-45) -1072629312*a(n-46) -1636386688*a(n-47) +676478848*a(n-48) +17783808*a(n-49) -33298432*a(n-50) +5111808*a(n-51) -524288*a(n-52)
|
|
|
EXAMPLE
|
Some solutions containing all values 0 to 4 for n=5
..0..0..3..0....0..3..0..0....0..0..0..0....1..2..2..2....2..2..2..1
..1..0..0..3....1..0..3..0....1..1..0..3....0..2..4..2....2..4..2..0
..2..2..2..0....2..2..2..0....2..2..2..0....0..2..2..2....2..2..2..0
..2..4..2..1....2..4..2..0....2..4..2..0....3..0..0..1....0..0..0..3
..2..2..2..1....2..2..2..1....2..2..2..0....0..0..0..0....0..3..0..0
|
|
|
CROSSREFS
|
|
|
|
KEYWORD
|
nonn
|
|
|
AUTHOR
|
|
|
|
STATUS
|
approved
|
| |
|
|
