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 11 results. Next

A229013 Number of arrays of median of three adjacent elements of some length-5 0..n array, with no adjacent equal elements in the latter.

Original entry on oeis.org

2, 15, 46, 101, 186, 307, 470, 681, 946, 1271, 1662, 2125, 2666, 3291, 4006, 4817, 5730, 6751, 7886, 9141, 10522, 12035, 13686, 15481, 17426, 19527, 21790, 24221, 26826, 29611, 32582, 35745, 39106, 42671, 46446, 50437, 54650, 59091, 63766, 68681, 73842
Offset: 1

Views

Author

R. H. Hardin, Sep 10 2013

Keywords

Examples

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

Crossrefs

Row 3 of A229012.

Formula

Empirical: a(n) = n^3 + 3*n^2 - 3*n + 1.
Conjectures from Colin Barker, Sep 13 2018: (Start)
G.f.: x*(2 - x)*(1 + 4*x + x^2) / (1 - x)^4.
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) for n>4.
(End)

A229006 Number of arrays of median of three adjacent elements of some length n+2 0..2 array, with no adjacent equal elements in the latter.

Original entry on oeis.org

3, 7, 15, 31, 57, 105, 193, 353, 653, 1209, 2241, 4161, 7719, 14325, 26581, 49311, 91489, 169729, 314881, 584177, 1083761, 2010609, 3730105, 6920121, 12838307, 23817773, 44187025, 81976335, 152083481, 282147169, 523442893, 971097649
Offset: 1

Views

Author

R. H. Hardin, Sep 10 2013

Keywords

Examples

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

Crossrefs

Column 2 of A229012.

Formula

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

A229007 Number of arrays of median of three adjacent elements of some length n+2 0..3 array, with no adjacent equal elements in the latter.

Original entry on oeis.org

4, 14, 46, 130, 332, 830, 2054, 5108, 12790, 32146, 80942, 203898, 513498, 1292934, 3254868, 8193210, 20623908, 51914372, 130680214, 328953874, 828059138, 2084434524, 5247046924, 13208134738, 33248182980, 83693989466, 210678694852
Offset: 1

Views

Author

R. H. Hardin, Sep 10 2013

Keywords

Comments

Column 3 of A229012.

Examples

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

Formula

Empirical: a(n) = 3*a(n-1) -5*a(n-3) +2*a(n-4) +11*a(n-5) -11*a(n-6) -2*a(n-7) +19*a(n-8) -8*a(n-9) -13*a(n-10) +28*a(n-11) -18*a(n-12) +a(n-13) +26*a(n-14) -24*a(n-15) +9*a(n-16) +15*a(n-17) -21*a(n-18) +13*a(n-19) +5*a(n-20) -12*a(n-21) +19*a(n-22) -9*a(n-23) -a(n-24) +4*a(n-25) -4*a(n-26) +2*a(n-27).

A229008 Number of arrays of median of three adjacent elements of some length n+2 0..4 array, with no adjacent equal elements in the latter.

Original entry on oeis.org

5, 23, 101, 359, 1145, 3527, 10735, 32907, 101635, 315579, 982305, 3059025, 9524031, 29640801, 92224095, 286910991, 892560177, 2776725201, 8638459639, 26874806287, 83609764417, 260117322353, 809247413805, 2517636208515, 7832571212121
Offset: 1

Views

Author

R. H. Hardin, Sep 10 2013

Keywords

Comments

Column 4 of A229012.

Examples

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

Formula

Empirical: a(n) = 4*a(n-1) -a(n-2) -10*a(n-3) +7*a(n-4) +35*a(n-5) -47*a(n-6) -9*a(n-7) +106*a(n-8) -43*a(n-9) -123*a(n-10) +248*a(n-11) -30*a(n-12) -255*a(n-13) +370*a(n-14) +13*a(n-15) -396*a(n-16) +484*a(n-17) +88*a(n-18) -609*a(n-19) +715*a(n-20) -62*a(n-21) -603*a(n-22) +830*a(n-23) -305*a(n-24) -450*a(n-25) +825*a(n-26) -580*a(n-27) -91*a(n-28) +586*a(n-29) -678*a(n-30) +304*a(n-31) +130*a(n-32) -423*a(n-33) +364*a(n-34) -103*a(n-35) -83*a(n-36) +176*a(n-37) -111*a(n-38) +25*a(n-39) +37*a(n-40) -32*a(n-41) +17*a(n-42) -2*a(n-43) -4*a(n-44) +2*a(n-45) -a(n-46).

A229009 Number of arrays of median of three adjacent elements of some length n+2 0..5 array, with no adjacent equal elements in the latter.

Original entry on oeis.org

6, 34, 186, 794, 3002, 10860, 38768, 139456, 506236, 1849846, 6780968, 24874236, 91221120, 334365156, 1225151856, 4488311694, 16442040398, 60232977210, 220660283800, 808393136582, 2961592442222, 10849984832400, 39749595896184
Offset: 1

Views

Author

R. H. Hardin, Sep 10 2013

Keywords

Comments

Column 5 of A229012.

Examples

			Some solutions for n=4
..5....1....5....2....4....5....0....1....3....1....1....3....0....5....2....4
..1....0....2....4....5....0....4....1....1....1....3....3....4....0....2....2
..3....4....3....4....1....3....1....3....4....4....2....3....2....5....3....5
..0....1....3....2....2....2....2....2....1....2....2....4....2....4....3....4
		

Formula

Empirical: a(n) = 5*a(n-1) -2*a(n-2) -20*a(n-3) +22*a(n-4) +82*a(n-5) -149*a(n-6) -43*a(n-7) +448*a(n-8) -234*a(n-9) -682*a(n-10) +1345*a(n-11) +224*a(n-12) -2593*a(n-13) +2526*a(n-14) +1704*a(n-15) -5131*a(n-16) +3300*a(n-17) +3626*a(n-18) -8749*a(n-19) +6357*a(n-20) +4147*a(n-21) -16222*a(n-22) +17531*a(n-23) -1049*a(n-24) -26481*a(n-25) +39209*a(n-26) -20438*a(n-27) -26566*a(n-28) +64130*a(n-29) -57341*a(n-30) +140*a(n-31) +70204*a(n-32) -97044*a(n-33) +51459*a(n-34) +41116*a(n-35) -107708*a(n-36) +100930*a(n-37) -16302*a(n-38) -75708*a(n-39) +115023*a(n-40) -67934*a(n-41) -19000*a(n-42) +85062*a(n-43) -80464*a(n-44) +25613*a(n-45) +34418*a(n-46) -57825*a(n-47) +36505*a(n-48) +585*a(n-49) -24392*a(n-50) +24406*a(n-51) -9363*a(n-52) -5285*a(n-53) +9392*a(n-54) -6018*a(n-55) +851*a(n-56) +2156*a(n-57) -2078*a(n-58) +767*a(n-59) +139*a(n-60) -384*a(n-61) +244*a(n-62) -37*a(n-63) -36*a(n-64) +32*a(n-65) -11*a(n-66) +2*a(n-68) -a(n-69)

A229010 Number of arrays of median of three adjacent elements of some length n+2 0..6 array, with no adjacent equal elements in the latter.

Original entry on oeis.org

7, 47, 307, 1527, 6635, 27379, 111311, 456029, 1888383, 7880975, 33018001, 138469191, 580547651, 2432537637, 10187801775, 42657765711, 178601463643, 747785468741, 3131002111003, 13109964303805, 54894127263817
Offset: 1

Views

Author

R. H. Hardin, Sep 10 2013

Keywords

Comments

Column 6 of A229012.

Examples

			Some solutions for n=4
..5....6....1....4....6....2....4....5....6....2....2....3....5....2....4....2
..6....3....2....3....3....6....3....5....1....2....6....2....4....1....0....5
..1....3....4....6....2....2....4....1....4....1....2....6....4....5....6....6
..3....2....5....5....2....6....2....3....4....3....3....2....2....4....3....5
		

Formula

Empirical recurrence of order 95 (see link above).

A229011 Number of arrays of median of three adjacent elements of some length n+2 0..7 array, with no adjacent equal elements in the latter.

Original entry on oeis.org

8, 62, 470, 2666, 13040, 60180, 273124, 1248872, 5780144, 26993340, 126638342, 594901860, 2793932346, 13112533536, 61505348386, 288407464930, 1352248997558, 6340299132898, 29728967922162, 139400729229576, 653670375108782
Offset: 1

Views

Author

R. H. Hardin, Sep 10 2013

Keywords

Comments

Column 7 of A229012.

Examples

			Some solutions for n=4
..0....4....2....1....3....3....6....2....3....2....1....5....6....0....6....1
..3....2....5....4....7....3....6....4....5....6....3....5....5....3....7....1
..2....2....3....0....0....1....7....1....5....0....1....4....6....0....2....7
..4....5....7....1....7....4....0....4....6....1....6....4....6....5....2....5
		

A229014 Number of arrays of median of three adjacent elements of some length 6 0..n array, with no adjacent equal elements in the latter.

Original entry on oeis.org

2, 31, 130, 359, 794, 1527, 2666, 4335, 6674, 9839, 14002, 19351, 26090, 34439, 44634, 56927, 71586, 88895, 109154, 132679, 159802, 190871, 226250, 266319, 311474, 362127, 418706, 481655, 551434, 628519, 713402, 806591, 908610, 1019999, 1141314
Offset: 1

Views

Author

R. H. Hardin, Sep 10 2013

Keywords

Examples

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

Crossrefs

Row 4 of A229012.

Formula

Empirical: a(n) = (2/3)*n^4 + (10/3)*n^3 - (5/3)*n^2 + (2/3)*n - 1.
Conjectures from Colin Barker, Sep 13 2018: (Start)
G.f.: x*(2 - x)*(1 + 11*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)

A229015 Number of arrays of median of three adjacent elements of some length 7 0..n array, with no adjacent equal elements in the latter.

Original entry on oeis.org

2, 57, 332, 1145, 3002, 6635, 13040, 23515, 39698, 63605, 97668, 144773, 208298, 292151, 400808, 539351, 713506, 929681, 1195004, 1517361, 1905434, 2368739, 2917664, 3563507, 4318514, 5195917, 6209972, 7375997, 8710410, 10230767
Offset: 1

Views

Author

R. H. Hardin, Sep 10 2013

Keywords

Examples

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

Crossrefs

Row 5 of A229012.

Formula

Empirical: a(n) = (19/60)*n^5 + (37/12)*n^4 + (19/12)*n^3 - (61/12)*n^2 + (31/10)*n - 1.
Conjectures from Colin Barker, Sep 13 2018: (Start)
G.f.: x*(2 + 45*x + 20*x^2 - 32*x^3 + 2*x^4 + x^5) / (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)

A229016 Number of arrays of median of three adjacent elements of some length 8 0..n array, with no adjacent equal elements in the latter.

Original entry on oeis.org

2, 105, 830, 3527, 10860, 27379, 60180, 119653, 220318, 381749, 629586, 996635, 1524056, 2262639, 3274168, 4632873, 6426970, 8760289, 11753990, 15548367, 20304740, 26207435, 33465852, 42316621, 53025846, 65891437, 81245530, 99456995
Offset: 1

Views

Author

R. H. Hardin, Sep 10 2013

Keywords

Examples

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

Crossrefs

Row 6 of A229012.

Formula

Empirical: a(n) = (11/90)*n^6 + (11/5)*n^5 + (167/36)*n^4 - (43/6)*n^3 + (583/180)*n^2 - (61/30)*n + 1.
Conjectures from Colin Barker, Sep 14 2018: (Start)
G.f.: x*(2 + 91*x + 137*x^2 - 148*x^3 - 4*x^4 + 9*x^5 + x^6) / (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)
Showing 1-10 of 11 results. Next