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 1-9 of 9 results.

A355913 Negasemiternary (or NST) representation of the unit ambinumber (1,0).

Original entry on oeis.org

2, 1, 1, 2, 0, 1, 0, 2, 2, 1, 1, 1, 1, 1, 1, 2, 2, 0, 2, 1, 2, 1, 2, 2, 0, 2, 0, 1, 0, 2, 1, 2, 1, 0, 0, 2, 2, 0, 1, 1, 1, 0, 1, 1, 0, 0, 2, 1, 2, 1, 0, 0, 1, 2, 1, 0, 1, 0, 2, 0, 1, 1, 0, 1, 0, 0, 0, 2, 0, 1, 2, 1, 2, 0, 1, 2
Offset: 1

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Author

N. J. A. Sloane, Sep 19 2022

Keywords

Examples

			(1, 0) = 2.11201 02211 11112 20212 12202 01021 ...
		

Crossrefs

A355905 Leftmost path in the tree T_0 of all negasemiternary (or NST) fractions whose 2-adic part is zero.

Original entry on oeis.org

0, 2, 1, 1, 0, 1, 1, 1, 1, 2, 1, 1, 0, 2, 1, 2, 0, 1, 0, 2, 0, 1, 1, 2, 0, 1, 0, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 1, 0, 1, 0, 1, 1, 2, 0, 1, 0, 1, 0, 2, 0, 1, 0, 1, 1, 2, 1, 2, 0, 1, 1, 2, 0, 1, 0, 2, 1, 2, 0, 2, 0, 2, 0, 2, 1, 2, 1, 1, 1, 2, 0, 1, 1, 1, 0, 2, 1, 2, 0, 1, 1
Offset: 0

Views

Author

N. J. A. Sloane, Sep 18 2022

Keywords

Comments

These are the edge labels in the tree. The initial a(0) = 0 is by convention.

Crossrefs

A355906 a(0) = 0; for n >= 1, a(n) = -(3/2)*(a(n-1)+A355905(n-1)).

Original entry on oeis.org

0, 0, -3, 3, -6, 9, -15, 21, -33, 48, -75, 111, -168, 252, -381, 570, -858, 1287, -1932, 2898, -4350, 6525, -9789, 14682, -22026, 33039, -49560, 74340, -111513, 167268, -250905, 376356, -564537, 846804, -1270209, 1905312, -2857971, 4286955, -6430434, 9645651
Offset: 0

Views

Author

N. J. A. Sloane, Sep 18 2022

Keywords

Comments

When n is odd, a(n) is the largest multiple of 3 whose NST representation has n digits. When n is even, a(n) is the smallest multiple of 3 with that property.

Crossrefs

Extensions

More terms from Jinyuan Wang, Sep 29 2022

A355907 A355906(n)/3.

Original entry on oeis.org

0, 0, -1, 1, -2, 3, -5, 7, -11, 16, -25, 37, -56, 84, -127, 190, -286, 429, -644, 966
Offset: 0

Views

Author

N. J. A. Sloane, Sep 18 2022

Keywords

Comments

This is also -(A355905(n)+A355906(n))/2.

Crossrefs

A355908 A335905(n) + A335906(n).

Original entry on oeis.org

0, 2, -2, 4, -6, 10, -14, 22, -32, 50, -74, 112, -168, 254, -380, 572, -858, 1288, -1932, 2900
Offset: 0

Views

Author

N. J. A. Sloane, Sep 19 2022

Keywords

Comments

This is also -2*A355907(n).

Crossrefs

A355909 Number of nodes at level n in the tree T_0 mentioned in A355905.

Original entry on oeis.org

1, 2, 3, 4, 6, 9, 13, 19, 28, 42, 63, 94, 141, 212, 318, 477, 716, 1074, 1611, 2417, 3626, 5439, 8158, 12237
Offset: 0

Views

Author

N. J. A. Sloane, Sep 19 2022

Keywords

Comments

First differences give A355910.

Crossrefs

Formula

a(n) = 1 + (c(n)+c(n-1))/2 where c(n) = |A355908(n)|.

A355910 Number of nodes at level n in the tree T_{-2}.

Original entry on oeis.org

1, 1, 1, 2, 3, 4, 6, 9, 14, 21, 31, 47, 71, 106, 159, 239, 358, 537, 806, 1209, 1813, 2719, 4079, 6119
Offset: 0

Views

Author

N. J. A. Sloane, Sep 19 2022

Keywords

Comments

First differences of A355909.

Crossrefs

A355911 Number of alt-unary-binary trees with n nodes.

Original entry on oeis.org

1, 1, 2, 2, 2, 4, 4, 4, 4, 6, 8, 8, 8, 8, 8, 12, 12, 14, 16, 16, 16, 16, 16, 16, 24, 24, 24, 26, 28, 28, 32, 32, 32, 32, 32, 32, 32, 40
Offset: 1

Views

Author

N. J. A. Sloane, Sep 19 2022

Keywords

Crossrefs

A355912 Negasemiternary (or NST) representation of the unit ambinumber (0,1).

Original entry on oeis.org

1, 2, 1, 1, 2, 2, 0, 0, 1, 1, 2, 1, 2, 1, 2, 0, 1, 0, 0, 2, 0, 2, 0, 1, 2, 1, 2, 2, 0, 0, 2, 0, 2, 0, 0, 0, 1, 2, 2, 1, 2, 0, 1, 2, 0, 0, 0, 2, 0, 2, 0, 2, 2, 0, 2, 2, 2, 2, 1, 0, 1, 2, 2, 2, 0, 0, 2, 1, 0, 1, 1, 1, 1, 0, 1, 1
Offset: 1

Views

Author

N. J. A. Sloane, Sep 19 2022

Keywords

Examples

			(0, 1) = 1.21122 00112 12120 10020 20121 22002 ...
		

Crossrefs

Showing 1-9 of 9 results.