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A240422
T(n,k)=Number of nXk 0..3 arrays with no element equal to two plus the sum of elements to its left or two plus the sum of the elements above it or two plus the sum of the elements diagonally to its northwest, modulo 4
5
3, 7, 7, 15, 35, 15, 31, 147, 147, 31, 63, 553, 1161, 553, 63, 127, 2045, 7857, 7857, 2045, 127, 255, 7439, 52711, 97269, 52711, 7439, 255, 511, 27099, 347155, 1197511, 1197511, 347155, 27099, 511, 1023, 98193, 2331517, 14516959, 27488435, 14516959
OFFSET
1,1
COMMENTS
Table starts
....3.......7........15..........31...........63...........127...........255
....7......35.......147.........553.........2045..........7439.........27099
...15.....147......1161........7857........52711........347155.......2331517
...31.....553......7857.......97269......1197511......14516959.....182716785
...63....2045.....52711.....1197511.....27488435.....619040901...14838256141
..127....7439....347155....14516959....619040901...26075879845.1191246174665
..255...27099...2331517...182716785..14838256141.1191246174665
..511...98193..15537761..2283795777.349768244657
.1023..356367.105095051.29455167803
.2047.1290555.706172043
LINKS
FORMULA
Empirical for column k:
k=1: a(n) = 3*a(n-1) -2*a(n-2)
k=2: [order 15]
k=3: [order 96] for n>100
EXAMPLE
Some solutions for n=4 k=4
..3..3..1..3....1..1..1..0....0..0..1..1....3..3..1..0....3..0..0..0
..3..0..0..2....1..0..1..1....0..3..0..2....3..0..0..0....0..0..3..0
..3..0..2..2....1..1..2..1....0..0..0..0....1..0..2..3....0..1..2..3
..1..0..0..0....0..1..1..3....0..3..0..3....3..0..0..0....0..1..0..2
CROSSREFS
Column 1 is A000225(n+1)
Sequence in context: A059478 A175329 A081218 * A130003 A098581 A238997
KEYWORD
nonn,tabl
AUTHOR
R. H. Hardin, Apr 04 2014
STATUS
approved