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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A298000 Solution of the complementary equation a(n) = a(1)*b(n) - a(0)*b(n-1) + 2*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, 10, 13, 16, 19, 22, 27, 29, 34, 36, 41, 43, 48, 50, 55, 57, 60, 63, 68, 72, 74, 77, 80, 85, 89, 91, 94, 97, 102, 106, 108, 111, 114, 119, 123, 125, 128, 131, 136, 140, 142, 147, 149, 154, 156, 159, 162, 167, 169, 172, 177, 181, 183, 188, 190, 195, 197
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.
Conjectures: a(n) - (2 +sqrt(2))*n < 4 for n >= 1. Guide to related sequences having initial values a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, b(2) = 5, where (b(n)) is the increasing sequence of positive integers not in (a(n)):
***
a(n) = a(1)*b(n) - a(0)*b(n-1) + n (a(n)) = A297999; (b(n)) = A298110
a(n) = a(1)*b(n) - a(0)*b(n-1) + 2*n (a(n)) = A298000; (b(n)) = A298111
a(n) = a(1)*b(n) - a(0)*b(n-1) + 3*n (a(n)) = A298001; (b(n)) = A298112
a(n) = a(1)*b(n) - a(0)*b(n-1) + 4*n (a(n)) = A298002; (b(n)) = A298113

Examples

			a(0) = 1, a(1) = 2, b(0) = 3, b(1) = 4, so that a(2) = 10.
Complement: (b(n)) = (3,4,5,6,8,9,11,12,14,15,17,18,20,...)
		

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4; b[2] = 5;
    a[n_] := a[n] = a[1]*b[n] - a[0]*b[n - 1] + 2 n;
    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}]  (* A298000 *)

A298113 Solution b( ) of the complementary equation a(n) = a(1)*b(n) - a(0)*b(n-1) + 4*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, 8, 9, 10, 11, 12, 13, 15, 16, 17, 18, 20, 21, 22, 23, 25, 26, 27, 28, 30, 31, 32, 33, 35, 36, 37, 38, 40, 41, 42, 43, 45, 46, 47, 48, 50, 51, 52, 53, 55, 56, 57, 58, 59, 60, 62, 63, 64, 66, 67, 68, 69, 71, 72, 73, 74, 76, 77, 78, 79, 80, 81
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 A298002. See A297830 for a guide to related sequences.
Conjecture: 1/2 < a(n) - n*sqrt(2) < 3 for n >= 1.

Crossrefs

Programs

  • Mathematica
    a[0] = 1; a[1] = 2; b[0] = 3; b[1] = 4; b[2] = 5;
    a[n_] := a[n] = a[1]*b[n] - a[0]*b[n - 1] + 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}]; (* A298002 *)
    v = Table[b[n], {n, 0, k}]; (* A298113 *)
    Take[u, 50]
    Take[v, 50]
Showing 1-2 of 2 results.