A207724
Number of n X 3 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 0 1 vertically.
Original entry on oeis.org
6, 36, 78, 189, 490, 1113, 2449, 5474, 12036, 26100, 56595, 122472, 264061, 568695, 1224190, 2633000, 5660226, 12165489, 26141850, 56165805, 120662377, 259206930, 556801480, 1196027864, 2569059663, 5518244160, 11852866905, 25459111647
Offset: 1
Some solutions for n=4:
1 1 0 1 1 1 1 0 0 1 0 0 0 1 1 0 1 1 0 0 1
1 0 1 1 1 1 1 0 0 1 1 1 0 1 1 1 1 1 1 1 1
1 0 0 1 1 0 1 0 0 1 0 0 1 1 1 0 1 1 0 0 1
1 1 0 1 0 0 1 1 1 1 0 0 0 0 1 0 1 1 0 0 1
- R. H. Hardin, Table of n, a(n) for n = 1..210
- Robert Israel, Maple-assisted proof of formula
- Index entries for linear recurrences with constant coefficients, signature (3,-2,3,-6,0,0,3,1,0,-1).
-
Configs:= select(A -> A[1..3] <> [0,0,0] and A[4..6] <> [0,0,0] and A[1..3] <> [0,1,0] and A[4..6] <> [0,1,0],
[seq(convert(x,base,2)[1..6],x=2^6..2^7-1)]):
compat:= proc(i,j) local k,col;
if Configs[i][4..6] <> Configs[j][1..3] then return 0 fi;
for k from 1 to 3 do
col:= [Configs[i][k],Configs[i][k+3],Configs[j][k+3]];
if col = [0,1,1] or col = [1,0,1] then return 0 fi;
od;
1
end proc:
T:= Matrix(36,36,compat):
u:= Vector[row](36, 1):
v:= Vector(36,1):
6,seq(u . T^(n-2) . v,n=2..50); # Robert Israel, Mar 05 2018
-
LinearRecurrence[{3, -2, 3, -6, 0, 0, 3, 1, 0, -1}, {6, 36, 78, 189, 490, 1113, 2449, 5474, 12036, 26100}, 30] (* Jean-François Alcover, May 15 2023, after Robert Israel's confirmed formula *)
A207730
Number of 3 X n 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 0 1 vertically.
Original entry on oeis.org
6, 36, 78, 169, 611, 2209, 6016, 16384, 51840, 164025, 478305, 1394761, 4249238, 12945604, 38516590, 114597025, 345332595, 1040643081, 3114412896, 9320743936, 27998628896, 84105220081, 252138754753, 755885919889, 2268515874246
Offset: 1
Some solutions for n=4:
..1..0..1..1....0..1..1..1....0..0..1..1....1..1..1..1....0..1..1..1
..0..0..1..1....1..1..1..1....1..1..1..1....0..0..1..1....0..1..1..1
..0..1..1..1....0..0..1..1....0..0..1..1....0..0..1..1....0..0..1..1
A207723
Number of n X n 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 0 1 vertically.
Original entry on oeis.org
2, 16, 78, 441, 8575, 277729, 4799749, 93547584, 8978585264, 1701743731081, 92421758243781, 5198831216732241, 3314060538084914409, 4426079717506620317769, 675694617961142291654422
Offset: 1
Some solutions for n=4
..0..1..1..0....0..0..1..1....1..0..1..1....1..1..1..1....1..1..0..0
..1..1..1..0....0..1..1..1....1..1..0..1....1..1..1..1....1..1..0..1
..0..1..1..1....1..0..1..1....1..0..0..1....1..1..1..1....1..1..0..0
..0..1..1..0....0..0..1..1....0..0..1..1....0..1..1..1....0..1..1..0
A207725
Number of n X 4 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 0 1 vertically.
Original entry on oeis.org
9, 81, 169, 441, 1225, 2809, 6241, 14161, 31329, 68121, 148225, 321489, 693889, 1495729, 3222025, 6932689, 14907321, 32046921, 68873401, 147987225, 317944561, 683038225, 1467273025, 3151811881, 6770162961, 14542189281, 31235967169
Offset: 1
Some solutions for n=4:
..1..1..1..0....1..1..0..0....0..0..1..1....1..0..0..1....1..1..0..0
..1..1..0..1....1..1..0..1....1..0..1..1....1..0..0..1....1..1..0..1
..1..1..0..0....1..1..1..0....0..1..1..1....1..1..0..1....1..1..0..0
..0..1..1..0....1..1..0..0....0..0..1..1....1..0..0..1....0..1..1..0
A207726
Number of nX5 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 0 1 vertically.
Original entry on oeis.org
15, 225, 611, 2163, 8575, 27931, 88243, 288813, 926949, 2927115, 9278885, 29390445, 92717065, 292337359, 921806095, 2904391209, 9147369231, 28808166663, 90713456051, 285607327515, 899181685831, 2830809676285, 8911643119525
Offset: 1
Some solutions for n=4
..1..0..1..1..1....1..0..1..1..1....1..0..1..1..0....0..0..1..1..0
..1..0..1..1..0....0..1..1..1..1....1..0..1..1..1....1..0..1..1..0
..1..0..1..1..0....0..0..1..1..1....0..0..1..1..0....0..1..1..1..1
..0..1..1..0..1....1..0..1..1..1....0..1..1..0..0....0..0..1..1..0
A207727
Number of nX6 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 0 1 vertically.
Original entry on oeis.org
25, 625, 2209, 10609, 60025, 277729, 1247689, 5890329, 27426169, 125776225, 580858201, 2686867225, 12388803025, 57136775089, 263724358681, 1216770043329, 5612971227241, 25896730187689, 119479087561201, 551206670239681
Offset: 1
Some solutions for n=4
..1..1..1..1..0..1....0..0..1..1..0..1....0..1..1..1..1..0....0..0..1..1..0..0
..1..1..1..1..1..1....1..1..1..1..0..0....1..1..1..1..1..1....1..0..1..1..1..1
..1..1..1..0..0..1....0..0..1..1..0..0....0..0..1..1..0..0....0..0..1..1..0..0
..1..1..1..0..0..1....0..0..1..1..0..0....0..0..1..1..0..0....0..1..1..1..0..0
A207728
Number of nX7 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 0 1 vertically.
Original entry on oeis.org
40, 1600, 6016, 33063, 211680, 1029231, 4799749, 23473944, 111527152, 517774120, 2415619129, 11251097760, 52094413065, 240990441237, 1114766044504, 5150494925352, 23781871171576, 109797744696883, 506801727014800
Offset: 1
Some solutions for n=4
..1..1..1..1..1..0..1....0..0..1..1..1..1..1....1..0..1..1..1..0..1
..1..0..1..1..0..0..1....1..1..1..1..0..0..1....0..1..1..1..1..0..1
..0..0..1..1..0..0..1....0..0..1..1..0..0..1....0..0..1..1..0..1..1
..0..1..1..0..1..1..0....0..0..1..1..1..0..1....0..0..1..1..0..0..1
A207731
Number of 4Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 0 1 vertically.
Original entry on oeis.org
9, 81, 189, 441, 2163, 10609, 33063, 103041, 418263, 1697809, 5875227, 20331081, 77333859, 294156801, 1057136187, 3799119769, 14123193995, 52502848225, 191262879795, 696752470089, 2569117858827, 9473043664561, 34677617171731
Offset: 1
Some solutions for n=4
..1..0..1..1....1..1..1..0....0..0..1..1....1..1..0..1....1..1..0..0
..1..1..1..1....0..1..1..1....0..1..1..1....1..1..0..1....1..1..0..1
..0..0..1..1....0..1..1..0....1..0..1..1....1..0..0..1....1..1..1..0
..0..0..1..1....1..1..0..0....0..0..1..1....1..0..0..1....1..1..0..0
A207732
Number of 5Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 0 1 vertically.
Original entry on oeis.org
14, 196, 490, 1225, 8575, 60025, 211680, 746496, 4078944, 22287841, 90968949, 371294361, 1833291198, 9052000164, 39384126042, 171355430401, 810254854919, 3831293402161, 17143608557024, 76711252182016, 355989323916384
Offset: 1
Some solutions for n=4
..0..1..1..1....1..0..1..1....1..1..1..0....0..0..1..1....0..1..1..1
..1..0..1..1....0..1..1..1....1..1..0..1....1..0..1..1....1..0..1..1
..0..0..1..1....0..0..1..1....1..1..0..0....0..0..1..1....0..0..1..1
..0..0..1..1....0..0..1..1....1..1..1..0....0..0..1..1....0..1..1..1
..1..0..0..1....0..1..1..1....1..0..0..1....0..0..1..1....1..0..0..1
A207733
Number of 6Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 1 1 and 1 0 1 vertically.
Original entry on oeis.org
21, 441, 1113, 2809, 27931, 277729, 1029231, 3814209, 27996255, 205492225, 919461235, 4114067881, 26135084283, 166026096369, 818513711715, 4035297528025, 23843629466995, 140886430854481, 730455853771371
Offset: 1
Some solutions for n=4
..1..0..0..1....1..0..1..1....1..1..0..1....1..0..1..1....0..1..1..0
..1..0..0..1....0..1..1..1....1..0..1..1....0..1..1..1....0..1..1..1
..1..1..0..1....0..0..1..1....1..0..0..1....0..0..1..1....0..1..1..0
..1..0..0..1....1..0..1..1....1..0..0..1....1..0..1..1....1..1..1..0
..1..0..0..1....0..0..1..1....1..1..0..1....0..1..1..1....0..1..1..0
..1..0..0..1....0..0..1..1....1..0..0..1....0..0..1..1....0..1..1..0
Showing 1-10 of 11 results.
Comments