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 17 results. Next

A296496 Decimal expansion of limiting power-ratio for A294414; see Comments.

Original entry on oeis.org

8, 8, 1, 4, 1, 0, 4, 6, 3, 2, 2, 0, 2, 5, 6, 5, 5, 2, 7, 9, 2, 5, 1, 8, 8, 3, 2, 2, 5, 8, 5, 4, 1, 2, 6, 7, 8, 5, 0, 8, 3, 6, 4, 9, 7, 9, 6, 8, 7, 2, 7, 4, 8, 4, 8, 8, 8, 3, 0, 9, 3, 6, 0, 3, 5, 4, 6, 5, 5, 5, 7, 7, 8, 9, 9, 6, 6, 4, 4, 2, 8, 3, 9, 0, 5, 3
Offset: 1

Views

Author

Clark Kimberling, Dec 20 2017

Keywords

Comments

Suppose that A = (a(n)), for n >= 0, is a sequence, and g is a real number such that a(n)/a(n-1) -> g. The ratio-sum for A is |a(1)/a(0) - g| + |a(2)/a(1) - g| + ..., assuming that this series converges. For A = A294414, we have g = (1 + sqrt(5))/2, the golden ratio (A001622). See the guide at A296469 for related sequences.

Examples

			limiting power-ratio = 8.814104632202565527925188322585412678508...
		

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 3; b[0] = 2; b[1] = 4;
    a[n_] := a[n] = a[n - 1] + a[n - 2] + b[n - 1] + b[n - 2];
    j = 1; While[j < 13, k = a[j] - j - 1;
    While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++];
    Table[a[n], {n, 0, k}]; (* A294414 *)
    z = 2000; g = GoldenRatio; h = Table[N[a[n]/g^n, z], {n, 0, z}];
    StringJoin[StringTake[ToString[h[[z]]], 41], "..."]
    Take[RealDigits[Last[h], 10][[1]], 120]   (* A296496 *)

A296495 Decimal expansion of ratio-sum for A294414; see Comments.

Original entry on oeis.org

4, 5, 8, 5, 1, 9, 7, 1, 7, 4, 1, 8, 4, 5, 6, 5, 4, 0, 1, 9, 8, 8, 8, 6, 9, 0, 5, 7, 8, 1, 7, 6, 5, 0, 7, 4, 6, 9, 0, 1, 6, 6, 0, 5, 6, 9, 3, 5, 9, 2, 0, 5, 5, 8, 2, 0, 4, 1, 4, 1, 6, 1, 7, 4, 4, 1, 3, 5, 2, 1, 8, 8, 5, 7, 5, 0, 6, 5, 1, 7, 9, 0, 7, 3, 7, 5
Offset: 1

Views

Author

Clark Kimberling, Dec 20 2017

Keywords

Comments

Suppose that A = (a(n)), for n >= 0, is a sequence, and g is a real number such that a(n)/a(n-1) -> g. The ratio-sum for A is |a(1)/a(0) - g| + |a(2)/a(1) - g| + ..., assuming that this series converges. For A = A294414, we have g = (1 + sqrt(5))/2, the golden ratio (A001622). See the guide at A296469 for related sequences.

Examples

			4.585197174184565401988869057817650746901...
		

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 3; b[0] = 2; b[1] = 4;
    a[n_] := a[n] = a[n - 1] + a[n - 2] + b[n - 1] + b[n - 2];
    j = 1; While[j < 13, k = a[j] - j - 1;
    While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++];
    Table[a[n], {n, 0, k}]; (* A294414 *)
    g = GoldenRatio; s = N[Sum[- g + a[n]/a[n - 1], {n, 1, 1000}], 200]
    Take[RealDigits[s, 10][[1]], 100]  (* A296495 *)

A296469 Decimal expansion of ratio-sum for A295862; see Comments.

Original entry on oeis.org

3, 8, 7, 0, 2, 3, 6, 0, 7, 9, 7, 9, 5, 9, 5, 9, 3, 2, 3, 2, 8, 2, 0, 5, 2, 3, 1, 1, 7, 8, 3, 9, 9, 5, 0, 1, 3, 8, 5, 6, 7, 3, 9, 8, 3, 0, 0, 9, 7, 2, 3, 1, 9, 9, 4, 3, 0, 1, 0, 8, 7, 6, 5, 5, 9, 5, 8, 0, 5, 4, 5, 4, 0, 6, 7, 3, 8, 5, 3, 9, 0, 5, 8, 8, 6, 2
Offset: 1

Views

Author

Clark Kimberling, Dec 18 2017

Keywords

Comments

Suppose that A = (a(n)), for n >= 0, is a sequence, and g is a real number such that a(n)/a(n-1) -> g. The ratio-sum for A is |a(1)/a(0) - g| + |a(2)/a(1) - g| + ..., assuming that this series converges. For A = A295862, we have g = (1 + sqrt(5))/2, the golden ratio (A001622). See A296425-A296434 for related ratio-sums and A296452-A296461 for related limiting power-ratios. Guide to more ratio-sums and limiting power-ratios:
****
Sequence A ratio-sum for A limiting power-ratio for A

Examples

			ratio-sum = 6.21032710946618494227967...
		

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 3; b[0] = 2; b[1 ] = 4; b[2] = 5;
    a[n_] := a[n] = a[n - 1] + a[n - 2] + b[n];
    j = 1; While[j < 13, k = a[j] - j - 1;
    While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++];
    Table[a[n], {n, 0, k}]; (* A295862 *)
    g = GoldenRatio; s = N[Sum[- g + a[n]/a[n - 1], {n, 1, 1000}], 200]
    Take[RealDigits[s, 10][[1]], 100]  (* A296469 *)

A294476 Solution of the complementary equation a(n) = a(n-2) + b(n-1) + 1, where a(0) = 1, a(1) = 3, b(0) = 2.

Original entry on oeis.org

1, 3, 6, 9, 14, 18, 25, 30, 38, 44, 54, 61, 72, 81, 93, 103, 116, 127, 141, 154, 169, 183, 199, 215, 232, 249, 267, 285, 304, 323, 344, 364, 386, 407, 430, 453, 477, 501, 526, 551, 577, 603, 630, 657, 686, 714, 744, 773, 804, 834, 867, 898, 932, 964, 999
Offset: 0

Views

Author

Clark Kimberling, Nov 01 2017

Keywords

Comments

The complementary sequences a() and b() are uniquely determined by the titular equation and initial values. The initial values of each sequence in the following guide are a(0) = 1, a(2) = 3, b(0) = 2:
A294476: a(n) = a(n-2) + b(n-1) + 1
A294477: a(n) = a(n-2) + b(n-1) + 2
A294478: a(n) = a(n-2) + b(n-1) + 3
A294479: a(n) = a(n-2) + b(n-1) + n
A294480: a(n) = a(n-2) + b(n-1) + 2n
A294481: a(n) = a(n-2) + b(n-1) + n - 1
A294482: a(n) = a(n-2) + b(n-1) + n + 1
For a(n-2) + b(n-1), with offset 1 instead of 0, see A022942.

Examples

			a(0) = 1, a(1) = 3, b(0) = 2, b(1) = 4, so that
a(2)  = a(0) + b(1) + 1 = 6
Complement: (b(n)) = (2, 4, 5, 7, 8, 10, 11, 12, 13, 15,...)
		

Crossrefs

Programs

  • Mathematica
    mex := First[Complement[Range[1, Max[#1] + 1], #1]] &;
    a[0] = 1; a[1] = 3; b[0] = 2;
    a[n_] := a[n] = a[n - 2] + b[n - 1] + 1;
    b[n_] := b[n] = mex[Flatten[Table[Join[{a[n]}, {a[i], b[i]}], {i, 0, n - 1}]]];
    Table[a[n], {n, 0, 40}]  (* A294476 *)
    Table[b[n], {n, 0, 10}]

A294413 Solution of the complementary equation a(n) = a(n-1) + a(n-2) - b(n-1) + 6, where a(0) = 1, a(1) = 3, b(0) = 2, b(1) = 4.

Original entry on oeis.org

1, 3, 6, 10, 15, 23, 35, 53, 82, 128, 202, 320, 511, 819, 1317, 2122, 3424, 5530, 8936, 14447, 23363, 37789, 61130, 98896, 160002, 258873, 418849, 677695, 1096516, 1774181, 2870666, 4644815, 7515448, 12160229, 19675642, 31835835
Offset: 0

Views

Author

Clark Kimberling, Oct 31 2017

Keywords

Comments

The complementary sequences a() and b() are uniquely determined by the titular equation and initial values. See A294414 for a guide to related sequences.
Conjecture: a(n)/a(n-1) -> (1 + sqrt(5))/2, the golden ratio.

Examples

			a(0) = 1, a(1) = 3, b(0) = 2, b(1) = 4, so that
a(2)  = a(1) + a(0) - b(1) + 6
Complement: (b(n)) = (2, 4, 6, 7, 9, 11, 12, 13, 14, 16, ...)
		

Crossrefs

Programs

  • Mathematica
    mex := First[Complement[Range[1, Max[#1] + 1], #1]] &;
    a[0] = 1; a[1] = 3; b[0] = 2; b[1] = 4;
    a[n_] := a[n] = a[n - 1] + a[n - 2] - b[n - 1] + 6;
    b[n_] := b[n] = mex[Flatten[Table[Join[{a[n]}, {a[i], b[i]}], {i, 0, n - 1}]]];
    Table[a[n], {n, 0, 40}]  (* A294413 *)
    Table[b[n], {n, 0, 10}]

A294415 Solution of the complementary equation a(n) = a(n-1) + a(n-2) + b(n-1) + b(n-2) + 1, where a(0) = 1, a(1) = 3, b(0) = 2, b(1) = 4.

Original entry on oeis.org

1, 3, 11, 24, 47, 85, 148, 251, 419, 693, 1138, 1859, 3027, 4918, 7979, 12933, 20950, 33923, 54915, 88882, 143843, 232774, 376669, 609497, 986222, 1595777, 2582059, 4177898, 6760021, 10937985, 17698074, 28636129, 46334275, 74970478, 121304829, 196275385
Offset: 0

Views

Author

Clark Kimberling, Oct 31 2017

Keywords

Comments

The complementary sequences a() and b() are uniquely determined by the titular equation and initial values. See A294414 for a guide to related sequences.
Conjecture: a(n)/a(n-1) -> (1 + sqrt(5))/2, the golden ratio.

Examples

			a(0) = 1, a(1) = 3, b(0) = 2, b(1) = 4, so that
a(2)  = a(1) + a(0) + b(1) + b(0) + 1 = 11
Complement: (b(n)) = (2, 4, 5, 6, 7, 8, 9, 10, 12, 13, 14,...)
		

Crossrefs

Programs

  • Mathematica
    mex := First[Complement[Range[1, Max[#1] + 1], #1]] &;
    a[0] = 1; a[1] = 3; b[0] = 2; b[1] = 4;
    a[n_] := a[n] = a[n - 1] + a[n - 2] + b[n - 1] + b[n - 2] + 1;
    b[n_] := b[n] = mex[Flatten[Table[Join[{a[n]}, {a[i], b[i]}], {i, 0, n - 1}]]];
    Table[a[n], {n, 0, 40}]  (* A294415 *)
    Table[b[n], {n, 0, 10}]

A294416 Solution of the complementary equation a(n) = a(n-1) + a(n-2) + b(n-1) + b(n-2) + n, where a(0) = 1, a(1) = 3, b(0) = 2, b(1) = 4.

Original entry on oeis.org

1, 3, 12, 27, 54, 99, 174, 297, 498, 825, 1357, 2220, 3618, 5882, 9547, 15479, 25079, 40614, 65752, 106428, 172245, 278741, 451057, 729872, 1181007, 1910961, 3092053, 5003102, 8095246, 13098442, 21193785, 34292327, 55486215, 89778648, 145264972, 235043732
Offset: 0

Views

Author

Clark Kimberling, Oct 31 2017

Keywords

Comments

The complementary sequences a() and b() are uniquely determined by the titular equation and initial values. See A294414 for a guide to related sequences.
Conjecture: a(n)/a(n-1) -> (1 + sqrt(5))/2, the golden ratio.

Examples

			a(0) = 1, a(1) = 3, b(0) = 2, b(1) = 4, so that
a(2)  = a(1) + a(0) + b(1) + b(0) + 2 = 12
Complement: (b(n)) = (2, 4, 5, 6, 7, 8, 9, 10, 11, 13, 14,...)
		

Crossrefs

Programs

  • Mathematica
    mex := First[Complement[Range[1, Max[#1] + 1], #1]] &;
    a[0] = 1; a[1] = 3; b[0] = 2; b[1] = 4;
    a[n_] := a[n] = a[n - 1] + a[n - 2] + b[n - 1] + b[n - 2] + n;
    b[n_] := b[n] = mex[Flatten[Table[Join[{a[n]}, {a[i], b[i]}], {i, 0, n - 1}]]];
    Table[a[n], {n, 0, 40}]  (* A294416 *)
    Table[b[n], {n, 0, 10}]

A294417 Solution of the complementary equation a(n) = a(n-1) + a(n-2) + b(n-1) + b(n-2) - n, where a(0) = 1, a(1) = 3, b(0) = 2, b(1) = 4.

Original entry on oeis.org

1, 3, 8, 17, 32, 57, 99, 168, 280, 462, 757, 1235, 2009, 3262, 5291, 8575, 13889, 22488, 36402, 58916, 95345, 154289, 249663, 403982, 653676, 1057690, 1711399, 2769123, 4480558, 7249719, 11730316, 18980075, 30710432, 49690549, 80401024, 130091617
Offset: 0

Views

Author

Clark Kimberling, Oct 31 2017

Keywords

Comments

The complementary sequences a() and b() are uniquely determined by the titular equation and initial values. See A294414 for a guide to related sequences.
Conjecture: a(n)/a(n-1) -> (1 + sqrt(5))/2, the golden ratio.

Examples

			a(0) = 1, a(1) = 3, b(0) = 2, b(1) = 4, so that
a(2)  = a(1) + a(0) + b(1) + b(0) - 2 = 8
Complement: (b(n)) = (2, 4, 5, 6, 7, 9, 10, 11, 13, 14,...)
		

Crossrefs

Programs

  • Mathematica
    mex := First[Complement[Range[1, Max[#1] + 1], #1]] &;
    a[0] = 1; a[1] = 3; b[0] = 2; b[1] = 4;
    a[n_] := a[n] = a[n - 1] + a[n - 2] + b[n - 1] + b[n - 2] - n;
    b[n_] := b[n] = mex[Flatten[Table[Join[{a[n]}, {a[i], b[i]}], {i, 0, n - 1}]]];
    Table[a[n], {n, 0, 40}]  (* A294417 *)
    Table[b[n], {n, 0, 10}]

A294418 Solution of the complementary equation a(n) = a(n-1) + a(n-2) + b(n-1) + 2*b(n-2), where a(0) = 1, a(1) = 3, b(0) = 2, b(1) = 4.

Original entry on oeis.org

1, 3, 12, 28, 56, 103, 181, 309, 518, 858, 1411, 2309, 3763, 6118, 9930, 16100, 26085, 42243, 68389, 110696, 179152, 289918, 469143, 759137, 1228359, 1987579, 3216026, 5203696, 8419816, 13623609, 22043525, 35667237, 57710868, 93378214, 151089194, 244467523
Offset: 0

Views

Author

Clark Kimberling, Oct 31 2017

Keywords

Comments

The complementary sequences a() and b() are uniquely determined by the titular equation and initial values. See A294414 for a guide to related sequences.
Conjecture: a(n)/a(n-1) -> (1 + sqrt(5))/2, the golden ratio.

Examples

			a(0) = 1, a(1) = 3, b(0) = 2, b(1) = 4, so that
a(2)  = a(1) + a(0) + b(1) + 2*b(0) = 12
Complement: (b(n)) = (2, 4, 5, 6, 7, 8, 9, 10, 11, 13, 14,...)
		

Crossrefs

Programs

  • Mathematica
    mex := First[Complement[Range[1, Max[#1] + 1], #1]] &;
    a[0] = 1; a[1] = 3; b[0] = 2; b[1] = 4;
    a[n_] := a[n] = a[n - 1] + a[n - 2] + b[n - 1] + 2 b[n - 2];
    b[n_] := b[n] = mex[Flatten[Table[Join[{a[n]}, {a[i], b[i]}], {i, 0, n - 1}]]];
    Table[a[n], {n, 0, 40}]  (* A294418 *)
    Table[b[n], {n, 0, 10}]

A294419 Solution of the complementary equation a(n) = a(n-1) + a(n-2) + 2*b(n-1) + 2*b(n-2), where a(0) = 1, a(1) = 3, b(0) = 2, b(1) = 4.

Original entry on oeis.org

1, 3, 16, 37, 75, 138, 243, 415, 696, 1153, 1895, 3098, 5047, 8203, 13314, 21587, 34975, 56640, 91697, 148423, 240210, 388727, 629035, 1017864, 1647005, 2664979, 4312098, 6977195, 11289415, 18266736, 29556281, 47823151, 77379570, 125202863, 202582581
Offset: 0

Views

Author

Clark Kimberling, Oct 31 2017

Keywords

Comments

The complementary sequences a() and b() are uniquely determined by the titular equation and initial values. See A294414 for a guide to related sequences.
Conjecture: a(n)/a(n-1) -> (1 + sqrt(5))/2, the golden ratio.

Examples

			a(0) = 1, a(1) = 3, b(0) = 2, b(1) = 4, so that
a(2)  = a(1) + a(0) + 2*b(1) + 2*b(0) = 16
Complement: (b(n)) = (2, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 17,...)
		

Crossrefs

Programs

  • Mathematica
    mex := First[Complement[Range[1, Max[#1] + 1], #1]] &;
    a[0] = 1; a[1] = 3; b[0] = 2; b[1] = 4;
    a[n_] := a[n] = a[n - 1] + a[n - 2] + 2 b[n - 1] + 2 b[n - 2];
    b[n_] := b[n] = mex[Flatten[Table[Join[{a[n]}, {a[i], b[i]}], {i, 0, n - 1}]]];
    Table[a[n], {n, 0, 40}]  (* A294419 *)
    Table[b[n], {n, 0, 10}]
Showing 1-10 of 17 results. Next