|
|
A229515
|
|
Number of n X 2 0..2 arrays of the median of the corresponding element, the element to the east and the element to the south in a larger (n+1) X 3 0..2 array without adjacent equal elements in the latter.
|
|
1
|
|
|
7, 33, 129, 481, 1751, 6433, 23507, 86295, 316099, 1159635, 4251051, 15590219, 57163723, 209618487, 768636943, 2818506063, 10335115437, 37897559703, 138965833325, 509570185111, 1868532243761, 6851675250519, 25124255606589
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
Column 2 of A229521.
|
|
LINKS
|
R. H. Hardin, Table of n, a(n) for n = 1..210
|
|
FORMULA
|
Empirical: a(n) = 2*a(n-1) + 8*a(n-2) - 7*a(n-3) - 4*a(n-4) + 19*a(n-5) - 17*a(n-6) + 20*a(n-7) - 12*a(n-8) + 17*a(n-9) + 3*a(n-10) + 13*a(n-11) + 16*a(n-12) - 7*a(n-13) + 2*a(n-14) + 8*a(n-15) -1 3*a(n-16) + 9*a(n-17) - 10*a(n-18) - a(n-19) + a(n-20).
|
|
EXAMPLE
|
Some solutions for n=3:
2 0 1 0 2 1 1 2 1 0 1 0 1 1 1 1 1 1 0 1
0 2 1 1 1 0 1 1 1 2 0 1 1 1 2 0 0 2 1 0
2 0 1 2 0 1 0 1 2 0 1 2 1 1 1 2 2 0 0 2
|
|
CROSSREFS
|
Cf. A229521.
Sequence in context: A215054 A350643 A114014 * A320907 A258458 A320546
Adjacent sequences: A229512 A229513 A229514 * A229516 A229517 A229518
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
R. H. Hardin, Sep 25 2013
|
|
STATUS
|
approved
|
|
|
|