cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-10 of 10 results.

A207249 Number of n X 3 0..1 arrays avoiding 0 0 1 and 1 0 1 horizontally and 0 1 0 and 1 0 1 vertically.

Original entry on oeis.org

6, 36, 102, 370, 1232, 4238, 14406, 49164, 167530, 571202, 1947168, 6638170, 22629802, 77146700, 262997994, 896578158, 3056494736, 10419796218, 35521783770, 121096145300, 412824884294, 1407347734502, 4797742864320
Offset: 1

Views

Author

R. H. Hardin, Feb 16 2012

Keywords

Comments

Column 3 of A207254.

Examples

			Some solutions for n=4:
..0..0..0....1..0..0....0..1..0....1..1..0....1..0..0....1..1..0....0..0..0
..0..1..1....0..0..0....1..0..0....1..0..0....1..0..0....0..0..0....1..0..0
..1..1..1....0..0..0....1..0..0....1..0..0....1..0..0....0..0..0....1..1..1
..1..0..0....0..1..0....1..1..0....0..1..1....1..0..0....1..0..0....0..1..1
		

Crossrefs

Cf. A207254.

Formula

Empirical: a(n) = 2*a(n-1) + 4*a(n-2) + 7*a(n-4) + 8*a(n-5) - a(n-8).
Empirical g.f.: 2*x*(3 + 12*x + 3*x^2 + 11*x^3 + 21*x^4 - 3*x^5 - 3*x^7) / (1 - 2*x - 4*x^2 - 7*x^4 - 8*x^5 + x^8). - Colin Barker, Feb 20 2018

A207248 Number of n X n 0..1 arrays avoiding 0 0 1 and 1 0 1 horizontally and 0 1 0 and 1 0 1 vertically.

Original entry on oeis.org

2, 16, 102, 940, 9072, 101036, 1231650, 16436824, 237255370, 3684061372, 61152471648, 1079792961548, 20191392448058, 398344602963240, 8263930584283206, 179759826117751524, 4089350929606635216
Offset: 1

Views

Author

R. H. Hardin Feb 16 2012

Keywords

Comments

Diagonal of A207254

Examples

			Some solutions for n=4
..1..1..0..0....1..1..0..0....1..1..0..0....1..1..1..1....0..0..0..0
..1..1..1..0....1..0..0..0....0..0..0..0....1..1..1..1....0..0..0..0
..1..1..1..0....0..0..0..0....0..0..0..0....1..1..1..1....1..0..0..0
..1..1..1..0....0..0..0..0....1..0..0..0....1..1..1..1....1..1..0..0
		

A207250 Number of n X 4 0..1 arrays avoiding 0 0 1 and 1 0 1 horizontally and 0 1 0 and 1 0 1 vertically.

Original entry on oeis.org

8, 64, 216, 940, 3776, 15652, 64176, 263976, 1084380, 4456764, 18314496, 75265524, 309304372, 1271098480, 5223614592, 21466618480, 88217749664, 362533690524, 1489843800060, 6122560903368, 25160860321572, 103399362536912
Offset: 1

Views

Author

R. H. Hardin, Feb 16 2012

Keywords

Comments

Column 4 of A207254.

Examples

			Some solutions for n=4:
..0..1..0..0....1..1..0..0....1..1..0..0....1..0..0..0....0..0..0..0
..1..1..1..0....0..0..0..0....1..1..0..0....0..0..0..0....0..0..0..0
..1..1..1..1....0..0..0..0....0..1..1..0....0..0..0..0....1..0..0..0
..0..1..1..1....1..0..0..0....0..1..1..0....1..0..0..0....1..1..0..0
		

Crossrefs

Cf. A207254.

Formula

Empirical: a(n) = 2*a(n-1) + 7*a(n-2) + 2*a(n-3) + 13*a(n-4) + 27*a(n-5) + 8*a(n-6) - 4*a(n-7) - 4*a(n-8) - 2*a(n-9) + a(n-10).
Empirical g.f.: 4*x*(2 + 12*x + 8*x^2 + 11*x^3 + 38*x^4 + 10*x^5 - 10*x^6 - 6*x^7 - 4*x^8 + 2*x^9) / (1 - 2*x - 7*x^2 - 2*x^3 - 13*x^4 - 27*x^5 - 8*x^6 + 4*x^7 + 4*x^8 + 2*x^9 - x^10). - Colin Barker, Jun 21 2018

A207251 Number of nX5 0..1 arrays avoiding 0 0 1 and 1 0 1 horizontally and 0 1 0 and 1 0 1 vertically.

Original entry on oeis.org

10, 100, 390, 1950, 9072, 43498, 206514, 982940, 4672690, 22223478, 105684192, 502611290, 2390250122, 11367287780, 54059152686, 257088257194, 1222630168560, 5814441801566, 27651641179470, 131502438430740, 625383900547134
Offset: 1

Views

Author

R. H. Hardin Feb 16 2012

Keywords

Comments

Column 5 of A207254

Examples

			Some solutions for n=4
..0..1..1..1..1....1..0..0..0..0....1..1..0..0..0....1..1..0..0..0
..1..1..0..0..0....0..0..0..0..0....1..0..0..0..0....1..0..0..0..0
..1..1..0..0..0....0..1..1..0..0....0..0..0..0..0....1..0..0..0..0
..1..0..0..0..0....0..1..1..0..0....0..0..0..0..0....1..0..0..0..0
		

Formula

Empirical: a(n) = 3*a(n-1) +6*a(n-2) +a(n-3) +36*a(n-4) +49*a(n-5) +31*a(n-6) +66*a(n-7) +45*a(n-8) +15*a(n-9) -5*a(n-10) -16*a(n-11) -a(n-12) -a(n-13) +a(n-14)

A207252 Number of nX6 0..1 arrays avoiding 0 0 1 and 1 0 1 horizontally and 0 1 0 and 1 0 1 vertically.

Original entry on oeis.org

12, 144, 636, 3560, 18688, 101036, 541380, 2906592, 15585680, 83611228, 448508160, 2406031628, 12906861916, 69237527840, 371416568460, 1992423747700, 10688138114240, 57335348257076, 307569175706760, 1649921069864080
Offset: 1

Views

Author

R. H. Hardin Feb 16 2012

Keywords

Comments

Column 6 of A207254

Examples

			Some solutions for n=4
..0..1..1..1..0..0....0..1..1..0..0..0....0..1..1..0..0..0....0..0..0..0..0..0
..1..0..0..0..0..0....0..0..0..0..0..0....0..1..0..0..0..0....1..1..0..0..0..0
..1..0..0..0..0..0....1..0..0..0..0..0....1..0..0..0..0..0....1..1..0..0..0..0
..0..1..1..0..0..0....1..0..0..0..0..0....1..0..0..0..0..0....0..1..1..0..0..0
		

Formula

Empirical: a(n) = 3*a(n-1) +9*a(n-2) +4*a(n-3) +58*a(n-4) +117*a(n-5) +100*a(n-6) +160*a(n-7) +169*a(n-8) +74*a(n-9) -12*a(n-10) -67*a(n-11) -26*a(n-12) +6*a(n-13) +3*a(n-14) +3*a(n-15) -a(n-16)

A207253 Number of nX7 0..1 arrays avoiding 0 0 1 and 1 0 1 horizontally and 0 1 0 and 1 0 1 vertically.

Original entry on oeis.org

14, 196, 966, 5950, 34608, 207298, 1231650, 7328836, 43552190, 258926454, 1539300960, 9151641190, 54407912390, 323463778900, 1923038207286, 11432757777574, 67969500563024, 404089167742226, 2402372140150290
Offset: 1

Views

Author

R. H. Hardin Feb 16 2012

Keywords

Comments

Column 7 of A207254

Examples

			Some solutions for n=4
..1..0..0..0..0..0..0....1..1..1..0..0..0..0....1..1..0..0..0..0..0
..0..1..0..0..0..0..0....0..0..0..0..0..0..0....0..1..1..0..0..0..0
..0..1..0..0..0..0..0....0..0..0..0..0..0..0....0..1..1..0..0..0..0
..1..1..1..1..0..0..0....0..0..0..0..0..0..0....1..0..0..0..0..0..0
		

Formula

Empirical: a(n) = 4*a(n-1) +7*a(n-2) +4*a(n-3) +102*a(n-4) +156*a(n-5) +223*a(n-6) +518*a(n-7) +545*a(n-8) +578*a(n-9) +532*a(n-10) +306*a(n-11) +173*a(n-12) -124*a(n-13) -147*a(n-14) -50*a(n-15) -14*a(n-16) +22*a(n-17) +a(n-18) +2*a(n-19) -a(n-20)

A207255 Number of 4 X n 0..1 arrays avoiding 0 0 1 and 1 0 1 horizontally and 0 1 0 and 1 0 1 vertically.

Original entry on oeis.org

10, 100, 370, 940, 1950, 3560, 5950, 9320, 13890, 19900, 27610, 37300, 49270, 63840, 81350, 102160, 126650, 155220, 188290, 226300, 269710, 319000, 374670, 437240, 507250, 585260, 671850, 767620, 873190, 989200, 1116310, 1255200, 1406570
Offset: 1

Views

Author

R. H. Hardin, Feb 16 2012

Keywords

Comments

Row 4 of A207254.

Examples

			Some solutions for n=4:
..0..0..0..0....1..0..0..0....0..1..0..0....1..1..1..1....0..1..0..0
..0..1..1..0....0..0..0..0....0..1..0..0....1..1..1..1....1..1..1..0
..0..1..1..0....0..0..0..0....1..0..0..0....1..1..1..1....1..1..1..1
..1..0..0..0....1..0..0..0....1..0..0..0....1..1..1..1....0..1..1..1
		

Crossrefs

Cf. A207254.

Formula

Empirical: a(n) = (5/6)*n^4 + (35/3)*n^3 - (5/6)*n^2 - (5/3)*n.
Conjectures from Colin Barker, Jun 21 2018: (Start)
G.f.: 10*x*(1 + 5*x - 3*x^2 - x^3) / (1 - x)^5.
a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n>5.
(End)

A207256 Number of 5 X n 0..1 arrays avoiding 0 0 1 and 1 0 1 horizontally and 0 1 0 and 1 0 1 vertically.

Original entry on oeis.org

16, 256, 1232, 3776, 9072, 18688, 34608, 59264, 95568, 146944, 217360, 311360, 434096, 591360, 789616, 1036032, 1338512, 1705728, 2147152, 2673088, 3294704, 4024064, 4874160, 5858944, 6993360, 8293376, 9776016, 11459392, 13362736
Offset: 1

Views

Author

R. H. Hardin, Feb 16 2012

Keywords

Comments

Row 5 of A207254.

Examples

			Some solutions for n=4:
..1..0..0..0....0..1..1..0....0..1..0..0....0..1..1..0....1..1..1..1
..0..1..1..0....1..1..0..0....1..1..1..0....0..1..1..1....1..1..0..0
..0..1..1..1....1..0..0..0....1..1..1..1....1..1..1..1....0..0..0..0
..1..1..1..1....0..0..0..0....0..1..1..1....1..0..0..0....0..0..0..0
..1..1..0..0....0..0..0..0....0..0..0..0....1..0..0..0....1..0..0..0
		

Crossrefs

Cf. A207254.

Formula

Empirical: a(n) = (4/15)*n^5 + (32/3)*n^4 + (44/3)*n^3 - (32/3)*n^2 + (16/15)*n.
Conjectures from Colin Barker, Jun 21 2018: (Start)
G.f.: 16*x*(1 + 10*x - 4*x^2 - 6*x^3 + x^4) / (1 - x)^6.
a(n) = 6*a(n-1) - 15*a(n-2) + 20*a(n-3) - 15*a(n-4) + 6*a(n-5) - a(n-6) for n>6.
(End)

A207257 Number of 6 X n 0..1 arrays avoiding 0 0 1 and 1 0 1 horizontally and 0 1 0 and 1 0 1 vertically.

Original entry on oeis.org

26, 676, 4238, 15652, 43498, 101036, 207298, 388232, 677898, 1119716, 1767766, 2688140, 3960346, 5678764, 7954154, 10915216, 14710202, 19508580, 25502750, 32909812, 41973386, 52965484, 66188434, 81976856, 100699690, 122762276
Offset: 1

Views

Author

R. H. Hardin, Feb 16 2012

Keywords

Comments

Row 6 of A207254.

Examples

			Some solutions for n=4:
..1..1..1..1....0..1..1..1....1..0..0..0....0..1..0..0....1..1..0..0
..1..1..1..1....1..1..0..0....1..1..0..0....1..0..0..0....1..0..0..0
..1..1..1..1....1..1..0..0....0..1..0..0....1..0..0..0....1..0..0..0
..1..1..1..0....1..0..0..0....0..0..0..0....1..0..0..0....1..1..1..1
..1..0..0..0....0..0..0..0....0..0..0..0....0..1..1..0....0..1..1..1
..1..0..0..0....0..1..1..0....0..0..0..0....0..1..1..0....0..0..0..0
		

Crossrefs

Cf. A207254.

Formula

Empirical: a(n) = (13/180)*n^6 + (143/20)*n^5 + (1235/36)*n^4 - (39/4)*n^3 - (377/45)*n^2 + (13/5)*n.
Conjectures from Colin Barker, Jun 21 2018: (Start)
G.f.: 26*x*(1 + 19*x + 2*x^2 - 28*x^3 + 7*x^4 + x^5) / (1 - x)^7.
a(n) = 7*a(n-1) - 21*a(n-2) + 35*a(n-3) - 35*a(n-4) + 21*a(n-5) - 7*a(n-6) + a(n-7) for n>7.
(End)

A207258 Number of 7 X n 0..1 arrays avoiding 0 0 1 and 1 0 1 horizontally and 0 1 0 and 1 0 1 vertically.

Original entry on oeis.org

42, 1764, 14406, 64176, 206514, 541380, 1231650, 2524704, 4777290, 8483748, 14307678, 23117136, 36023442, 54423684, 80047002, 115004736, 161844522, 223608420, 303895158, 406926576, 537618354, 701655108, 905569938, 1156828512
Offset: 1

Views

Author

R. H. Hardin, Feb 16 2012

Keywords

Comments

Row 7 of A207254.

Examples

			Some solutions for n=4:
..1..0..0..0....1..0..0..0....1..1..1..0....0..0..0..0....1..0..0..0
..1..1..0..0....1..0..0..0....0..1..1..1....0..1..1..1....1..1..0..0
..1..1..0..0....1..0..0..0....0..1..1..1....0..1..1..1....0..1..0..0
..0..1..1..0....0..1..1..0....1..1..0..0....1..1..0..0....0..0..0..0
..0..1..1..0....0..1..1..0....1..0..0..0....1..0..0..0....1..0..0..0
..0..1..0..0....0..1..0..0....0..0..0..0....1..0..0..0....1..1..0..0
..0..1..0..0....0..1..0..0....0..0..0..0....0..1..0..0....0..1..0..0
		

Crossrefs

Cf. A207254.

Formula

Empirical: a(n) = (1/60)*n^7 + (77/20)*n^6 + (2527/60)*n^5 + (119/4)*n^4 - (644/15)*n^3 + (42/5)*n^2 + (4/5)*n.
Conjectures from Colin Barker, Jun 21 2018: (Start)
G.f.: 42*x*(1 + 34*x + 35*x^2 - 96*x^3 + 15*x^4 + 14*x^5 - x^6) / (1 - x)^8.
a(n) = 8*a(n-1) - 28*a(n-2) + 56*a(n-3) - 70*a(n-4) + 56*a(n-5) - 28*a(n-6) + 8*a(n-7) - a(n-8) for n>8.
(End)
Showing 1-10 of 10 results.