login
Search: a199149 -id:a199149
     Sort: relevance | references | number | modified | created      Format: long | short | data
Number of n X 1 0..3 arrays with values 0..3 introduced in row major order and each element equal to one or two horizontal and vertical neighbors.
+10
3
0, 1, 1, 2, 3, 6, 11, 23, 47, 102, 221, 492, 1099, 2485, 5637, 12858, 29391, 67354, 154539, 355003, 816035, 1876862, 4318201, 9937840, 22874731, 52659593, 121237417, 279141170, 642732027, 1479959118, 3407837387, 7847200511
OFFSET
1,4
COMMENTS
Column 1 of A199149.
LINKS
FORMULA
Empirical: a(n) = 3*a(n-1) + a(n-2) - 7*a(n-3) + a(n-4) + 3*a(n-5) for n>6.
Empirical g.f.: x^2*(1 - 2*x - 2*x^2 + 3*x^3 + x^4) / ((1 - x)*(1 - x - x^2)*(1 - x - 3*x^2)). - Colin Barker, Feb 22 2018
EXAMPLE
Some solutions for n=8:
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..0....0....0....0....0....0....0....0....0....0....0....0....0....0....0....0
..1....0....0....1....1....1....0....1....1....0....1....0....0....0....1....0
..1....1....0....1....1....1....1....1....1....0....1....0....0....0....1....0
..2....1....1....1....1....0....1....2....1....0....2....1....0....1....1....0
..2....1....1....0....2....0....0....2....1....1....2....1....0....1....1....0
..2....0....0....0....2....1....0....1....0....1....3....1....0....2....2....1
..2....0....0....0....2....1....0....1....0....1....3....1....0....2....2....1
CROSSREFS
Cf. A199149.
KEYWORD
nonn
AUTHOR
R. H. Hardin, Nov 03 2011
STATUS
approved
Number of nX2 0..3 arrays with values 0..3 introduced in row major order and each element equal to one or two horizontal and vertical neighbors
+10
1
1, 3, 13, 65, 393, 2539, 16866, 113432, 766473, 5188597, 35148945, 238173743, 1614066774, 10938730576, 74134306725, 502428413393, 3405102418833, 23077383280435, 156402287318610, 1059984943413152, 7183834447992225
OFFSET
1,2
COMMENTS
Column 2 of A199149
LINKS
FORMULA
Empirical: a(n) = 7*a(n-1) +2*a(n-2) -16*a(n-3) -49*a(n-4) -35*a(n-5) +56*a(n-6) +54*a(n-7) +45*a(n-8) -27*a(n-9) for n>11
EXAMPLE
Some solutions for n=4
..0..0....0..0....0..0....0..0....0..1....0..1....0..0....0..1....0..1....0..0
..0..1....0..0....1..2....1..0....0..1....0..1....1..0....0..1....0..1....0..1
..1..1....1..1....1..2....1..0....1..1....0..1....1..0....1..2....0..0....0..1
..0..0....0..0....1..1....1..1....2..2....1..1....1..0....1..2....1..1....0..1
KEYWORD
nonn
AUTHOR
R. H. Hardin Nov 03 2011
STATUS
approved
Number of nX3 0..3 arrays with values 0..3 introduced in row major order and each element equal to one or two horizontal and vertical neighbors
+10
1
1, 13, 132, 2453, 42420, 794416, 14511531, 268456338, 4940928443, 91146218920, 1679743067872, 30969409565822, 570877041856787, 10524153072061784, 194006638767664141, 3576453618832667684, 65930406443303698229
OFFSET
1,2
COMMENTS
Column 3 of A199149
LINKS
FORMULA
Empirical: a(n) = 14*a(n-1) +120*a(n-2) -646*a(n-3) -1320*a(n-4) +3562*a(n-5) +12682*a(n-6) +1896*a(n-7) -76623*a(n-8) +36670*a(n-9) +19724*a(n-10) -245388*a(n-11) +53233*a(n-12) +2738818*a(n-13) -138967*a(n-14) -11411168*a(n-15) +3626519*a(n-16) +17979294*a(n-17) -10633666*a(n-18) -27553810*a(n-19) +19090457*a(n-20) +20077526*a(n-21) -32139160*a(n-22) +46609580*a(n-23) +115127457*a(n-24) +146403730*a(n-25) +50426678*a(n-26) -122760336*a(n-27) -143444310*a(n-28) -587979162*a(n-29) -679787397*a(n-30) -166474764*a(n-31) -212565465*a(n-32) +6372918*a(n-33) +256248603*a(n-34) +47278566*a(n-35) -708588*a(n-36) -12754584*a(n-37) for n>38
EXAMPLE
Some solutions for n=4
..0..1..1....0..1..1....0..1..1....0..0..0....0..1..1....0..0..1....0..0..0
..0..1..2....0..0..0....0..2..0....0..1..1....0..2..2....2..2..1....1..1..0
..3..3..2....2..2..0....2..2..0....2..3..2....1..0..3....1..1..0....0..0..1
..1..1..1....3..3..3....2..0..0....2..3..2....1..0..3....2..2..0....0..1..1
KEYWORD
nonn
AUTHOR
R. H. Hardin Nov 03 2011
STATUS
approved
Number of nX4 0..3 arrays with values 0..3 introduced in row major order and each element equal to one or two horizontal and vertical neighbors
+10
1
2, 65, 2453, 125468, 6235011, 316561994, 15958823113, 806680624447, 40736752748774, 2057896226081573, 103945296750116087, 5250572116269762125, 265216743260845702081, 13396704712673136390007, 676696655003807234547723
OFFSET
1,1
COMMENTS
Column 4 of A199149
LINKS
EXAMPLE
Some solutions for n=3
..0..0..1..1....0..0..1..1....0..1..1..1....0..1..0..0....0..0..1..1
..2..2..2..3....1..2..3..1....0..2..3..0....0..1..0..2....0..0..2..2
..0..0..3..3....1..2..3..3....0..2..3..0....1..1..2..2....2..2..0..0
KEYWORD
nonn
AUTHOR
R. H. Hardin Nov 03 2011
STATUS
approved
Number of nX5 0..3 arrays with values 0..3 introduced in row major order and each element equal to one or two horizontal and vertical neighbors
+10
1
3, 393, 42420, 6235011, 839006010, 117380324984, 16158623337745, 2239304268913257, 309471298054332806, 42818034223579225138, 5921413251810033475103, 819050117505774849777870
OFFSET
1,1
COMMENTS
Column 5 of A199149
LINKS
EXAMPLE
Some solutions for n=3
..0..0..0..0..1....0..0..1..1..1....0..0..1..1..1....0..0..1..0..0
..2..1..2..2..1....2..0..3..3..1....2..1..1..2..3....2..2..1..1..1
..2..1..2..1..1....2..3..3..2..2....2..0..0..2..3....0..0..2..2..2
KEYWORD
nonn
AUTHOR
R. H. Hardin Nov 03 2011
STATUS
approved
Number of n X n 0..3 arrays with values 0..3 introduced in row major order and each element equal to one or two horizontal and vertical neighbors
+10
0
0, 3, 132, 125468, 839006010, 44832664800117
OFFSET
1,2
COMMENTS
Diagonal of A199149
EXAMPLE
Some solutions for n=4
..0..0..1..1....0..0..1..1....0..0..1..1....0..1..1..1....0..0..1..1
..1..1..0..0....2..2..3..3....1..1..1..0....0..0..2..2....2..3..3..0
..2..2..0..3....2..2..0..0....2..0..0..0....2..2..3..2....2..0..0..0
..0..0..3..3....0..0..2..2....2..2..2..2....1..1..3..2....3..3..3..3
KEYWORD
nonn
AUTHOR
R. H. Hardin Nov 03 2011
STATUS
approved
Number of nX6 0..3 arrays with values 0..3 introduced in row major order and each element equal to one or two horizontal and vertical neighbors
+10
0
6, 2539, 794416, 316561994, 117380324984, 44832664800117, 16925667317073175
OFFSET
1,1
COMMENTS
Column 6 of A199149
EXAMPLE
Some solutions for n=3
..0..1..1..1..1..2....0..0..1..2..3..3....0..1..0..0..2..2....0..0..1..1..1..2
..0..1..0..2..1..2....0..1..1..2..0..3....0..1..1..0..2..2....1..1..3..3..0..2
..0..1..0..2..1..1....0..0..0..0..0..3....0..0..1..3..3..3....1..1..0..0..0..2
KEYWORD
nonn
AUTHOR
R. H. Hardin Nov 03 2011
STATUS
approved
Number of nX7 0..3 arrays with values 0..3 introduced in row major order and each element equal to one or two horizontal and vertical neighbors
+10
0
11, 16866, 14511531, 15958823113, 16158623337745, 16925667317073175
OFFSET
1,1
COMMENTS
Column 7 of A199149
EXAMPLE
Some solutions for n=3
..0..0..1..2..2..0..1....0..0..0..1..2..0..0....0..0..1..0..2..3..0
..0..1..1..3..0..0..1....0..1..0..1..2..2..2....0..1..1..0..2..3..0
..0..0..3..3..2..2..1....0..1..0..1..1..3..3....0..0..0..0..1..1..0
KEYWORD
nonn
AUTHOR
R. H. Hardin Nov 03 2011
STATUS
approved

Search completed in 0.074 seconds