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.

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A297999 Solution (a(n)) of the near-complementary equation a(n) = a(1)*b(n) - a(0)*b(n-1) + n, where a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, , b(2) = 5, and (b(n)) is the increasing sequence of positive integers not in (a(n)). See Comments.

Original entry on oeis.org

1, 2, 8, 10, 12, 16, 19, 22, 23, 25, 29, 30, 34, 35, 41, 43, 44, 46, 52, 52, 54, 60, 60, 62, 64, 66, 70, 75, 77, 78, 80, 82, 84, 88, 91, 92, 94, 96, 98, 102, 105, 108, 111, 112, 114, 118, 119, 121, 123, 127, 132, 134, 137, 140, 141, 143, 147, 148, 154, 156
Offset: 0

Views

Author

Clark Kimberling, Feb 09 2018

Keywords

Comments

The sequence (a(n)) generated by the equation a(n) = a(1)*b(n) - a(0)*b(n-1) + n, with initial values as shown, includes duplicates; e.g. a(18) = a(19) = 52. If the duplicates are removed from (a(n)), the resulting sequence and (b(n)) are complementary. Conjectures:
(1) 0 <= a(k) - a(k-1) <= 6 for k>=1;
(2) if d is in {0,1,2,3,4,5,6}, then a(k) = a(k-1) + d for infinitely many k.
***
See A298000 and A297830 for guides to related sequences.

Examples

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

Crossrefs

Programs

  • Mathematica
    mex[list_, start_] := (NestWhile[# + 1 &, start, MemberQ[list, #] &]);
    a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4; b[2] = 5;
    a[n_] := a[1]*b[n] - a[0]*b[n - 1] + n;
    Table[{a[n], b[n + 1] = mex[Flatten[Map[{a[#], b[#]} &, Range[0, n]]], b[n - 0]]}, {n, 2, 3000}];
    Table[a[n], {n, 0, 150}]  (* A297999 *)
    Table[b[n], {n, 0, 150}]  (* A298110 *)
    (* Peter J. C. Moses, Jan 16 2018 *)

A298110 Solution (b(n)) of the near-complementary equation a(n) = a(1)*b(n) - a(0)*b(n-1) + n, where a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, b(2) = 5, and (b(n)) is the increasing sequence of positive integers not in (a(n)). See Comments.

Original entry on oeis.org

3, 4, 5, 6, 7, 9, 11, 13, 14, 15, 17, 18, 20, 21, 24, 26, 27, 28, 31, 32, 33, 36, 37, 38, 39, 40, 42, 45, 47, 48, 49, 50, 51, 53, 55, 56, 57, 58, 59, 61, 63, 65, 67, 68, 69, 71, 72, 73, 74, 76, 79, 81, 83, 85, 86, 87, 89, 90, 93, 95, 97, 99, 100, 101, 103
Offset: 0

Views

Author

Clark Kimberling, Feb 09 2018

Keywords

Comments

The sequence (a(n)) generated by the equation a(n) = a(1)*b(n-1) - a(0)*b(n-2) + n, with initial values as shown, includes duplicates; e.g. a(18) = a(19) = 51. If the duplicates are removed from (a(n)), the resulting sequence and (b(n)) are complementary. Conjectures:
(1) 1 <= b(k) - b(k-1) <= 3 for k>=1;
(2) if d is in {1,2,3}, then b(k) = b(k-1) + d for infinitely many k.
***
See A298000 and A297830 for guides to related sequences.

Examples

			a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, b(2) = 5, so that a(2) = 8.
Complement: A298110 = (3,4,5,6,7,9,11,13,14,15,17, ...)
		

Crossrefs

Programs

  • Mathematica
    mex[list_, start_] := (NestWhile[# + 1 &, start, MemberQ[list, #] &]);
    a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4; b[2] = 5;
    a[n_] := a[1]*b[n] - a[0]*b[n - 1] + n;
    Table[{a[n], b[n + 1] = mex[Flatten[Map[{a[#], b[#]} &, Range[0, n]]], b[n - 0]]}, {n, 2, 3000}];
    Table[a[n], {n, 0, 150}]  (* A297999 *)
    Table[b[n], {n, 0, 150}]  (* A298110 *)
    (* Peter J. C. Moses, Jan 16 2018 *)

A298469 a(n) = a(0)*b(n) + a(1)*b(n-1), where a(0) = 1, a(1) = 3, b(0) = 2; b(1) = 4 ; b(2) = 5.

Original entry on oeis.org

1, 3, 17, 21, 25, 29, 33, 37, 41, 45, 49, 53, 57, 61, 66, 73, 77, 82, 89, 93, 98, 105, 109, 114, 121, 125, 130, 137, 141, 146, 153, 157, 162, 169, 173, 178, 185, 189, 194, 201, 205, 210, 217, 221, 226, 233, 237, 242, 249, 253, 257
Offset: 0

Views

Author

Clark Kimberling, Feb 11 2018

Keywords

Comments

The increasing complementary sequences a() and b() are uniquely determined by the titular equation and initial values. See A297830 for a guide to related sequences.

Examples

			a(2) = 1*5 + 3*4 = 17.
		

Crossrefs

Programs

  • Mathematica
    mex[list_, start_] := (NestWhile[# + 1 &, start, MemberQ[list, #] &]);
    aCoeffs = {1, 3}; bCoeffs = {2, 4, 5};
    Table[a[n - 1] = #[[n]], {n, Length[#]}] &[aCoeffs];
    Table[b[n - 1] = #[[n]], {n, Length[#]}] &[bCoeffs];
    a[n_] := Hold[Sum[a[z] b[n - z], {z, 0, Length[aCoeffs] - 1}]]
    Table[{a[z] = ReleaseHold[a[z]], b[z + 1] =
        mex[Join[Table[a[n], {n, 0, z}], Table[b[n], {n, 0, z}]], 1]}, {z,
        Length[aCoeffs], 1000}];
    Table[a[n], {n, 0, 50}]  (* A298469 *)
    Table[b[n], {n, 0, 50}]  (* complement *)
    (* Peter J. C. Moses, Jan 19 2018 *)

A297835 Solution of the complementary equation a(n) = a(1)*b(n-1) - a(0)*b(n-2) + 2*n + 1, where a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, and (b(n)) is the increasing sequence of positive integers not in (a(n)). See Comments.

Original entry on oeis.org

1, 2, 10, 13, 16, 19, 22, 25, 30, 32, 37, 39, 44, 46, 51, 53, 58, 60, 65, 67, 70, 73, 78, 82, 84, 87, 90, 95, 99, 101, 104, 107, 112, 116, 118, 121, 124, 129, 133, 135, 138, 141, 146, 150, 152, 155, 158, 163, 167, 169, 174, 176, 181, 183, 186, 189, 194, 196
Offset: 0

Views

Author

Clark Kimberling, Feb 04 2018

Keywords

Comments

The increasing complementary sequences a() and b() are uniquely determined by the titular equation and initial values. See A297830 for a guide to related sequences.
Conjecture: a(n) - (2 +sqrt(2))*n < 7 for n >= 1.

Examples

			a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, so that a(2) = 10.
Complement: (b(n)) = (3,4,6,7,8,9,11,12,14,15,17,18,20,...)
		

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4;
    a[n_] := a[n] = a[1]*b[n - 1] - a[0]*b[n - 2] + 2 n + 1;
    j = 1; While[j < 100, k = a[j] - j - 1;
     While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++]; k
    Table[a[n], {n, 0, k}]  (* A297835 *)

A297998 Solution of the complementary equation a(n) = a(1)*b(n-1) - a(0)*b(n-2) + floor(5*n/2), where a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, and (b(n)) is the increasing sequence of positive integers not in (a(n)). See Comments.

Original entry on oeis.org

1, 2, 10, 13, 17, 20, 24, 27, 33, 35, 41, 43, 47, 52, 55, 60, 63, 66, 72, 74, 80, 82, 86, 89, 93, 98, 103, 105, 109, 112, 116, 121, 126, 128, 132, 137, 140, 143, 147, 152, 155, 160, 163, 166, 170, 175, 178, 183, 186, 191, 194, 197, 201, 204, 210, 214, 217
Offset: 0

Views

Author

Clark Kimberling, Feb 04 2018

Keywords

Comments

The increasing complementary sequences a() and b() are uniquely determined by the titular equation and initial values.

Examples

			a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, so that a(2) = 10.
Complement: (b(n)) = (3,4,5,6,7,8,9,11,12,14,15,16,18,19,21,...)
		

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4;
    a[n_] := a[n] = a[1]*b[n - 1] - a[0]*b[n - 2] + Floor[5/2];
    j = 1; While[j < 100, k = a[j] - j - 1;
     While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++]; k
    Table[a[n], {n, 0, k}]  (* A297998 *)

A298003 Solution b( ) of the complementary equation a(n) = a(1)*b(n-1) - a(0)*b(n-2) + 2*n, where a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, and (b(n)) is the increasing sequence of positive integers not in (a(n)). See Comments.

Original entry on oeis.org

3, 4, 5, 6, 7, 8, 10, 11, 13, 14, 16, 17, 19, 20, 22, 23, 24, 25, 27, 29, 30, 31, 32, 34, 36, 37, 38, 39, 41, 43, 44, 45, 46, 48, 50, 51, 52, 53, 55, 57, 58, 60, 61, 63, 64, 65, 66, 68, 69, 70, 72, 74, 75, 77, 78, 80, 81, 82, 83, 85, 86, 87, 89, 91, 92, 94
Offset: 0

Views

Author

Clark Kimberling, Feb 08 2018

Keywords

Comments

The increasing complementary sequences a() and b() are uniquely determined by the titular equation and initial values. The solution a( ) is given at A297830, which includes a guide to related sequences.
Conjecture: 3/5 < a(n) - n*sqrt(2)*n < 3 for n >= 1.

Crossrefs

Cf. A297830.

Programs

  • Mathematica
    a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4;
    a[n_] := a[n] = a[1]*b[n - 1] - a[0]*b[n - 2] + 2 n;
    j = 1; While[j < 80000, k = a[j] - j - 1;
    While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++]; k
    u = Table[a[n], {n, 0, k}]; (* A297830 *)
    v = Table[b[n], {n, 0, k}]; (* A298003 *)
    Take[u, 50]
    Take[v, 50]

A298004 Solution b( ) of the complementary equation a(n) = a(1)*b(n-1) - a(0)*b(n-2) + 3*n, where a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, and (b(n)) is the increasing sequence of positive integers not in (a(n)). See Comments.

Original entry on oeis.org

3, 4, 5, 6, 7, 8, 9, 10, 12, 13, 14, 16, 17, 18, 20, 21, 22, 24, 25, 26, 28, 29, 30, 32, 33, 34, 36, 37, 38, 39, 40, 42, 43, 45, 46, 47, 49, 50, 51, 52, 53, 55, 56, 58, 59, 60, 62, 63, 64, 65, 66, 68, 69, 71, 72, 73, 75, 76, 77, 78, 79, 81, 82, 84, 85, 86
Offset: 0

Views

Author

Clark Kimberling, Feb 09 2018

Keywords

Comments

The increasing complementary sequences a() and b() are uniquely determined by the titular equation and initial values. The solution a( ) is given at A297836. See A297830 for a guide to related sequences.
Conjecture: 7/10 < a(n) - n*L < 3 for n >= 1, where L = (-1 + sqrt(13))/2.

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4;
    a[n_] := a[n] = a[1]*b[n - 1] - a[0]*b[n - 2] + 3 n;
    j = 1; While[j < 80000, k = a[j] - j - 1;
    While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++]; k
    u = Table[a[n], {n, 0, k}]; (* A297836 *)
    v = Table[b[n], {n, 0, k}]; (* A298004 *)
    Take[u, 50]
    Take[v, 50]

A298005 Solution b( ) of the complementary equation a(n) = a(1)*b(n-1) - a(0)*b(n-2) + 4*n, where a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, and (b(n)) is the increasing sequence of positive integers not in (a(n)). See Comments.

Original entry on oeis.org

3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 19, 20, 21, 22, 24, 25, 26, 27, 29, 30, 31, 32, 34, 35, 36, 37, 39, 40, 41, 42, 44, 45, 46, 47, 49, 50, 51, 52, 54, 55, 56, 57, 58, 59, 61, 62, 63, 65, 66, 67, 68, 70, 71, 72, 73, 75, 76, 77, 78, 79, 80, 82
Offset: 0

Views

Author

Clark Kimberling, Feb 09 2018

Keywords

Comments

The increasing complementary sequences a() and b() are uniquely determined by the titular equation and initial values. The solution a( ) is given at A297837. See A297830 for a guide to related sequences.
Conjecture: 7/10 < a(n) - n*L < 3 for n >= 1, where L = -1 + sqrt(5).

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4;
    a[n_] := a[n] = a[1]*b[n - 1] - a[0]*b[n - 2] + 4 n;
    j = 1; While[j < 80000, k = a[j] - j - 1;
     While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++]; k
    u = Table[a[n], {n, 0, k}]; (* A297837 *)
    v = Table[b[n], {n, 0, k}]; (* A298005 *)
    Take[u, 50]
    Take[v, 50]

A298006 Solution b( ) of the complementary equation a(n) = a(1)*b(n-1) - a(0)*b(n-2) + 2*n - 1, where a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, and (b(n)) is the increasing sequence of positive integers not in (a(n)). See Comments.

Original entry on oeis.org

3, 4, 5, 6, 7, 9, 10, 12, 13, 15, 16, 18, 19, 20, 21, 23, 25, 26, 27, 28, 30, 32, 33, 34, 35, 37, 39, 40, 41, 42, 44, 46, 47, 49, 50, 52, 53, 54, 55, 57, 58, 59, 61, 63, 64, 66, 67, 69, 70, 71, 72, 74, 75, 76, 78, 80, 81, 83, 84, 86, 87, 88, 89, 91, 92, 93
Offset: 0

Views

Author

Clark Kimberling, Feb 09 2018

Keywords

Comments

The increasing complementary sequences a() and b() are uniquely determined by the titular equation and initial values. The solution a( ) is given at A297831. See A297830 for a guide to related sequences.
Conjecture: 9/10 < a(n) - n*sqrt(2) < 3 for n >= 1.

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4;
    a[n_] := a[n] = a[1]*b[n - 1] - a[0]*b[n - 2] + 2 n - 1;
    j = 1; While[j < 80000, k = a[j] - j - 1;
     While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++]; k
    u = Table[a[n], {n, 0, k}]; (* A297831 *)
    v = Table[b[n], {n, 0, k}]; (* A298006 *)
    Take[u, 50]
    Take[v, 50]

A298007 Solution b( ) of the complementary equation a(n) = a(1)*b(n-1) - a(0)*b(n-2) + 2*n - 2, where a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, and (b(n)) is the increasing sequence of positive integers not in (a(n)). See Comments.

Original entry on oeis.org

3, 4, 5, 6, 8, 9, 11, 12, 14, 15, 16, 17, 19, 21, 22, 23, 24, 26, 28, 29, 30, 31, 33, 35, 36, 38, 39, 41, 42, 43, 44, 46, 47, 48, 50, 52, 53, 55, 56, 58, 59, 60, 61, 63, 64, 65, 67, 69, 70, 72, 73, 75, 76, 77, 78, 80, 81, 82, 84, 86, 87, 88, 89, 91, 93, 94
Offset: 0

Views

Author

Clark Kimberling, Feb 09 2018

Keywords

Comments

The increasing complementary sequences a() and b() are uniquely determined by the titular equation and initial values. The solution a( ) is given at A297832. See A297830 for a guide to related sequences.
Conjecture: 1 < a(n) - n*sqrt(2) < 3 for n >= 1.

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4;
    a[n_] := a[n] = a[1]*b[n - 1] - a[0]*b[n - 2] + 2 n - 2;
    j = 1; While[j < 80000, k = a[j] - j - 1;
     While[k < a[j + 1] - j + 1, b[k] = j + k + 2; k++]; j++]; k
    u = Table[a[n], {n, 0, k}]; (* A297832 *)
    v = Table[b[n], {n, 0, k}]; (* A298007 *)
    Take[u, 50]
    Take[v, 50]
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