|
|
A241397
|
|
T(n,k)=Number of nXk 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of the elements above it or zero plus the sum of the elements diagonally to its northwest or one plus the sum of the elements antidiagonally to its northeast, modulo 4
|
|
11
|
|
|
2, 2, 3, 4, 5, 4, 6, 9, 13, 7, 8, 23, 29, 28, 10, 14, 44, 85, 97, 64, 15, 20, 93, 201, 480, 340, 142, 24, 30, 204, 689, 1657, 2780, 1156, 318, 35, 48, 368, 1929, 8697, 15339, 17211, 4068, 726, 54, 70, 761, 4068, 31654, 129985, 160947, 102782, 14763, 1634, 83, 108
(list;
table;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,1
|
|
COMMENTS
|
Table starts
..2....2......4........6..........8..........14..........20.........30
..3....5......9.......23.........44..........93.........204........368
..4...13.....29.......85........201.........689........1929.......4068
..7...28.....97......480.......1657........8697.......31654......92204
.10...64....340.....2780......15339......129985......667050....2949778
.15..142...1156....17211.....160947.....2234804....18589398..134190457
.24..318...4068...102782....1622867....39781828...541660724.7518340973
.35..726..14763...645484...18627122...821631365.21331876978
.54.1634..52950..3936420..196990531.16108803423
.83.3695.190950.24633252.2356216195
|
|
LINKS
|
|
|
FORMULA
|
Empirical for column k:
k=1: a(n) = a(n-2) +2*a(n-3)
k=2: [order 38]
Empirical for row n:
n=1: a(n) = a(n-2) +2*a(n-3)
n=2: [order 22] for n>23
|
|
EXAMPLE
|
Some solutions for n=4 k=4
..3..2..3..3....3..2..2..2....2..3..3..2....2..3..3..2....2..3..3..2
..1..2..1..2....2..1..0..0....2..1..2..0....2..3..2..2....1..3..1..2
..3..2..0..0....3..1..2..0....3..0..0..2....2..0..0..3....1..2..0..2
..1..0..0..0....3..2..0..0....2..0..1..0....2..1..1..3....3..2..2..2
|
|
CROSSREFS
|
|
|
KEYWORD
|
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|