|
|
A206171
|
|
Number of 3 X (n+1) 0..3 arrays with every 2 X 2 subblock in a row having an equal number of equal diagonal or equal antidiagonal elements, adjacent rows differing in this number, and new values 0..3 introduced in row major order.
|
|
1
|
|
|
102, 1070, 14182, 196078, 2728486, 38016046, 529805350, 7383933550, 102911463910, 1434302337070, 19990233287398, 278608949740270, 3883043657285542, 54118965415458862, 754269763387561894
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
|
|
LINKS
|
|
|
FORMULA
|
Empirical: a(n) = 16*a(n-1) - 21*a(n-2) - 120*a(n-3) + 153*a(n-4) + 216*a(n-5) - 243*a(n-6).
Empirical g.f.: 2*x*(51 - 281*x - 398*x^2 + 1938*x^3 + 927*x^4 - 2997*x^5) / ((1 - x)*(1 - 3*x)*(1 - 3*x^2)*(1 - 12*x - 27*x^2)). - Colin Barker, Jun 14 2018
|
|
EXAMPLE
|
Some solutions for n=4:
0 0 0 0 0 0 0 0 0 1 0 1 1 1 0 0 0 0 0 0
0 1 0 2 0 0 2 0 1 2 0 0 1 0 2 0 1 0 1 0
2 1 3 1 1 1 3 0 1 2 3 3 3 3 1 1 0 1 0 1
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|