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 1-4 of 4 results.

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

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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.

Links

Crossrefs

Cf. A355904, A355905, A355907-A355913.

Extensions

More terms from Jinyuan Wang, Sep 29 2022

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.

Links

Crossrefs

Cf. A355904-A355908, A355910-A355913.

Formula

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

A355904 Negasemiternary (or NST) representation of n.

Original entry on oeis.org

0, 1, 2, 210, 211, 212, 21120, 21121, 21122, 21100, 21101, 21102, 2112010, 2112011, 2112012, 2112220, 2112221, 2112222, 2112200, 2112201, 2112202, 2110110, 2110111, 2110112, 211201020, 211201021, 211201022, 211201000, 211201001, 211201002, 211201210, 211201211, 211201212, 211222120, 211222121, 211222122
Offset: 0

Views

Author

N. J. A. Sloane, Sep 18 2022

Keywords

References

  • L. Rossi and J. Thuswaldner, A number system with base -3/2, American Mathematical Monthly, vol. 129, (June--July 2022), 539-553.

Links

Crossrefs

Cf. A355905-A355913.

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.

Links

Crossrefs

Cf. A355904-A355906, A355908-A355913.
Showing 1-4 of 4 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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