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 1-7 of 7 results.

A197531 Number of n X 2 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,0,1,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

3, 9, 16, 33, 73, 160, 361, 835, 1966, 4703, 11399, 27914, 68903, 171121, 426940, 1068865, 2682789, 6746336, 16988333, 42822747, 108024178, 272648551, 688426371, 1738750602, 4392467427, 11098043841, 28043540864, 70868720569, 179102669081
Offset: 1

Views

Author

R. H. Hardin, Oct 16 2011

Keywords

Comments

Every 0 is next to 0 2's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's.
Column 2 of A197537.

Examples

			Some solutions for n=4:
..1..0....1..0....0..1....1..0....1..1....2..1....0..0....0..1....2..1....0..0
..1..0....2..1....1..1....1..1....0..0....1..0....0..0....1..1....1..0....0..3
..1..1....2..1....1..0....0..1....0..3....1..0....0..0....1..0....1..1....0..0
..0..1....1..0....1..0....1..2....0..0....2..1....1..1....2..1....0..1....0..0
		

Crossrefs

Cf. A197537.

Formula

Empirical: a(n) = 3*a(n-1) - a(n-3) - 4*a(n-4) - 3*a(n-5) + a(n-7) + a(n-8).
Empirical g.f.: x*(1 + x)^2*(3 - 6*x - 2*x^2 - 2*x^3 + x^4 + 2*x^5) / ((1 - x - x^2 - x^3)*(1 - 2*x - x^2 - x^3 + x^5)). - Colin Barker, Mar 02 2018

A197532 Number of nX3 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,0,1,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

4, 16, 56, 216, 868, 3500, 14085, 56842, 229706, 928664, 3755722, 15191220, 61451640, 248596817, 1005703793, 4068662528, 16460279703, 66592450774, 269410213656, 1089943115100, 4409547400430, 17839571907124, 72173035560719
Offset: 1

Views

Author

R. H. Hardin Oct 16 2011

Keywords

Comments

Every 0 is next to 0 2's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's
Column 3 of A197537

Examples

			Some solutions for n=4
..0..0..1....1..0..0....0..0..0....0..3..0....1..1..1....1..0..0....0..0..0
..1..1..1....2..3..0....3..0..3....0..0..3....0..0..0....1..0..3....0..0..3
..1..1..0....1..0..0....0..3..0....3..0..0....3..0..3....2..3..0....0..0..0
..0..1..1....1..0..0....1..2..1....0..3..0....0..0..0....1..0..0....1..1..1
		

Formula

Empirical: a(n) = 4*a(n-1) +5*a(n-2) -15*a(n-3) -21*a(n-4) +3*a(n-5) +28*a(n-6) +32*a(n-7) -5*a(n-8) -57*a(n-9) +10*a(n-10) +90*a(n-11) +44*a(n-12) -14*a(n-13) -101*a(n-14) -56*a(n-15) +46*a(n-16) +14*a(n-17) +11*a(n-18) -20*a(n-19) +9*a(n-20) +10*a(n-21) -9*a(n-22) -a(n-25)

A197533 Number of nX4 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,0,1,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

5, 33, 216, 1419, 9373, 62586, 423085, 2879723, 19671764, 134643523, 922592723, 6325665762, 43386843099, 297644913045, 2042157812212, 14012277918367, 96148923597911, 659765081841360, 4527301927394765, 31066516652385893
Offset: 1

Views

Author

R. H. Hardin Oct 16 2011

Keywords

Comments

Every 0 is next to 0 2's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's
Column 4 of A197537

Examples

			Some solutions containing all values 0 to 4 for n=5
..0..3..0..0....0..3..0..0....0..3..0..0....1..0..3..0....2..1..2..1
..3..0..3..1....0..0..0..0....3..0..4..0....1..0..0..3....1..0..3..0
..0..4..0..1....3..0..4..0....0..4..0..3....1..0..4..0....1..0..0..0
..0..0..3..2....0..3..0..0....0..0..3..0....2..3..0..3....1..0..4..0
..0..3..0..1....1..2..1..1....1..1..2..1....1..0..0..0....1..0..0..0
		

Formula

Empirical: a(n) = 8*a(n-1) +4*a(n-2) -79*a(n-3) -30*a(n-4) +99*a(n-5) +41*a(n-6) +263*a(n-7) -405*a(n-8) +899*a(n-9) +7150*a(n-10) +6933*a(n-11) +8469*a(n-12) -2881*a(n-13) -45032*a(n-14) -44677*a(n-15) -82181*a(n-16) -77611*a(n-17) -25835*a(n-18) +35284*a(n-19) +242999*a(n-20) +361557*a(n-21) +412582*a(n-22) +192680*a(n-23) -167729*a(n-24) -442796*a(n-25) -480857*a(n-26) -373624*a(n-27) -111734*a(n-28) -57452*a(n-29) -25481*a(n-30) +186675*a(n-31) -47892*a(n-32) +194240*a(n-33) +243447*a(n-34) +94789*a(n-35) +253036*a(n-36) -22990*a(n-37) -5434*a(n-38) -112176*a(n-39) -176692*a(n-40) -20055*a(n-41) -59142*a(n-42) -41241*a(n-43) +34876*a(n-44) -30663*a(n-45) +12856*a(n-46) +1495*a(n-47) +26166*a(n-48) +13268*a(n-49) +10725*a(n-50) +8787*a(n-51) -4719*a(n-52) +2299*a(n-53) -1952*a(n-54) +414*a(n-55) +118*a(n-56) -729*a(n-57) -38*a(n-58) -281*a(n-59) -97*a(n-60) -73*a(n-61) -40*a(n-62) -34*a(n-63) -24*a(n-64) -8*a(n-65) -2*a(n-66)

A197534 Number of nX5 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,0,1,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

9, 73, 868, 9373, 107655, 1220630, 14056707, 162042137, 1874230689, 21698542215, 251403042154, 2913819348602, 33779087426950, 391635814747885, 4540933400612193, 52653016886940873, 610534294176601038
Offset: 1

Views

Author

R. H. Hardin Oct 16 2011

Keywords

Comments

Every 0 is next to 0 2's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's
Column 5 of A197537

Examples

			Some solutions containing all values 0 to 4 for n=4
..1..0..0..0..0....0..0..1..1..2....0..3..0..0..1....0..0..0..0..0
..1..0..4..0..0....0..0..3..0..1....3..0..4..0..1....0..4..0..3..0
..2..3..0..0..3....0..4..0..3..2....0..3..0..3..2....3..0..0..1..1
..1..0..0..3..0....0..0..3..0..1....1..1..0..0..1....0..3..0..1..2
		

A197535 Number of n X 6 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,0,1,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

16, 160, 3500, 62586, 1220630, 23325250, 454280983, 8844380028, 172982554332, 3386294190736, 66356347688978, 1300795127521094, 25506585069158562, 500211695453958433, 9810478953775130079, 192417797960470740096
Offset: 1

Views

Author

R. H. Hardin, Oct 16 2011

Keywords

Comments

Every 0 is next to 0 2's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's.
Column 6 of A197537.

Examples

			Some solutions containing all values 0 to 4 for n=4:
..0..0..0..0..3..0....1..1..1..1..2..1....0..0..0..3..0..1....1..1..2..1..1..1
..3..0..0..4..0..0....0..0..0..0..3..0....0..0..4..0..3..2....0..0..3..0..0..0
..0..3..0..0..3..0....0..0..0..4..0..0....0..0..0..0..0..1....3..0..0..4..0..3
..1..2..1..1..2..1....0..0..3..0..3..0....0..3..0..0..0..1....0..0..0..0..3..0
		

Crossrefs

Cf. A197537.

A197536 Number of nX7 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 2,0,1,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

25, 361, 14085, 423085, 14056707, 454280983, 14991391782, 493785636151, 16343961543732, 541269402906501, 17943273862788427, 595019891173209941, 19736497896904338854, 654726724059190203302, 21721092108797190824889
Offset: 1

Views

Author

R. H. Hardin Oct 16 2011

Keywords

Comments

Every 0 is next to 0 2's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's
Column 7 of A197537

Examples

			Some solutions containing all values 0 to 4 for n=4
..0..0..3..0..3..0..0....0..3..0..3..0..1..2....1..0..0..0..0..1..2
..0..3..0..0..0..0..0....3..0..0..0..0..1..1....1..3..0..3..1..1..1
..1..1..0..4..0..0..3....0..4..0..3..1..1..0....0..0..4..0..3..0..0
..2..1..0..0..0..3..0....0..0..3..0..1..1..0....0..0..0..3..0..0..0
		

A197530 Number of n X n 0..4 arrays with each element x equal to the number of its horizontal and vertical neighbors equal to 2,0,1,0,0 for x=0,1,2,3,4.

Original entry on oeis.org

1, 9, 56, 1419, 107655, 23325250, 14991391782, 27504159228709, 145843735771766573
Offset: 1

Views

Author

R. H. Hardin Oct 16 2011

Keywords

Comments

Every 0 is next to 0 2's, every 1 is next to 1 0's, every 2 is next to 2 1's, every 3 is next to 3 0's, every 4 is next to 4 0's
Diagonal of A197537

Examples

			Some solutions containing all values 0 to 4 for n=4
..0..0..0..1....1..0..0..0....1..2..1..1....0..0..0..0....1..0..0..0
..3..0..3..2....1..0..4..0....0..3..0..0....3..0..4..0....2..3..0..0
..0..4..0..1....2..3..0..0....0..0..4..0....0..3..0..0....1..0..4..0
..0..0..0..1....1..0..3..0....0..0..0..0....1..2..1..1....1..0..0..0
		
Showing 1-7 of 7 results.