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.

A114611 Eventual period of the RATS sequence, where 0 indicates a divergent sequence.

Original entry on oeis.org

0, 0, 8, 0, 0, 8, 0, 0, 2, 0, 0, 8, 0, 0, 8, 0, 0, 2, 0, 0, 8, 0, 0, 8, 0, 0, 2, 0, 18, 8, 0, 0, 8, 0, 0, 2, 0, 18, 8, 0, 0, 8, 0, 0, 2, 0, 18, 8, 18, 0, 8, 0, 0, 2, 0, 18, 8, 18, 0, 8, 0, 0, 2, 0, 18, 8, 18, 0, 2, 0, 0, 2, 0, 18, 8, 18, 0, 2, 0, 0, 2, 0, 18, 8, 18, 0, 2, 0, 0, 2, 0, 18, 8, 18, 0, 2
Offset: 1

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Author

Eric W. Weisstein, Dec 16 2005

Keywords

Comments

a(A001651(n)) = 0; a(A114612(n)) = 2; a(A114613(n)) = 3; a(A114614(n)) = 8; a(A114615(n)) = 14; a(A114616(n)) = 18. - Reinhard Zumkeller, Mar 14 2012
Row 10 of A288537. - Andrey Zabolotskiy, Jun 14 2017

Crossrefs

A161593 Lengths of new periods in the RATS sequence (0 replacing infinity).

Original entry on oeis.org

0, 8, 2, 18, 2, 2, 2, 14, 2, 3, 2, 2, 2, 6
Offset: 1

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Author

J. H. Conway and Tanya Khovanova, Jun 14 2009

Keywords

Comments

The values A114611(j) for those starting values j of the RATS mapping x->A036839(x) which end in cycles that cannot be reached starting from any smaller j.
Every integer > 1 appears in this sequence. - Andrey Zabolotskiy, Jun 11 2017
For other terms see Branicky link. - Michael S. Branicky, Dec 30 2022

Examples

			a(1)=A114611(0). a(2)=A114611(j=3)=8 with a cycle of length 8 shown in A066710.
A114611(j=6)=8 does not contribute because the cycle is the same as reached from j=3.
a(3)=A114611(9)=2 with a new cycle of length 2 shown in A066711.
A114611(j=12)=8 does not contribute because the cycle is the same as reached from j=3.
A114611(j=15)=8 does not contribute because 15->66->123 is the cycle as reached from j=3.
A114611(j=18)=2 does not contribute because the cycle is the same as reached from j=9.
A114611(j=21)=8 does not contribute because 21->33->66 reaches the same cycle as started from j=3.
a(4)=A114611(j=29)=18.
		

Crossrefs

Extensions

Comment and examples added by R. J. Mathar, Jul 07 2009
a(9)-a(14) from Michael S. Branicky, Dec 30 2022

A288535 Array RATS(b,n) by upward antidiagonals: Reverse Add Then Sort digits of n>0 in base b>1.

Original entry on oeis.org

1, 2, 3, 2, 4, 3, 2, 1, 4, 3, 2, 4, 6, 8, 3, 2, 4, 6, 5, 4, 3, 2, 4, 1, 8, 10, 8, 7, 2, 4, 6, 8, 6, 15, 4, 3, 2, 4, 6, 8, 10, 12, 5, 14, 3, 2, 4, 6, 1, 10, 7, 18, 10, 4, 15, 2, 4, 6, 8, 10, 12, 14, 24, 15, 8, 3, 2, 4, 6, 8, 10, 12, 8, 21, 6, 5, 4, 15, 2, 4, 6
Offset: 2

Views

Author

Andrey Zabolotskiy, Jun 11 2017

Keywords

Examples

			17 in base 3 is 122, 122+221=1120->112 which is 14 in decimal, thus RATS(3,17)=14.
The array begins:
1, 3, 3, 3,  3,  3,  7, ...
2, 4, 4, 8,  4,  8,  4, ...
2, 1, 6, 5, 10, 15,  5, ...
2, 4, 6, 8,  6, 12, 18, ...
2, 4, 1, 8, 10,  7, 14, ...
		

Crossrefs

Programs

  • Mathematica
    rats[n_, b_: 10] := FromDigits[Sort[IntegerDigits[n + FromDigits[Reverse[IntegerDigits[n, b]], b], b]], b];
    Flatten[Table[rats[n, s + 2 - n], {s, 20}, {n, s}]]

A288536 The eventual period of the RATS sequence in base n starting from 1; 0 is for infinity.

Original entry on oeis.org

1, 3, 2, 2, 8, 4, 3, 2, 0, 28, 90, 8, 72, 3, 4, 2, 64, 0, 18, 4, 18, 20, 396, 8, 160, 120, 18, 6, 28, 4, 5, 2, 210, 384, 240, 0, 648, 1242, 240, 4, 660, 18, 798, 380, 852, 1298, 1771, 8, 0, 160, 16, 372, 520, 1404, 1740, 6, 36, 2072, 1856, 380, 300, 215, 6, 2, 3384, 50, 2310, 3784, 2904
Offset: 2

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Author

Andrey Zabolotskiy, Jun 11 2017

Keywords

Comments

Eventual period of 1 under the mapping x->A288535(n,x), or 0 if there is a divergence and thus no eventual period.
Column 1 of A288537.
In Thiel's terms, the zeroes a(10), a(19), and a(37) correspond to quasiperiodic divergent RATS sequences with quasiperiod 2, while a(50)=0 corresponds to a sequence with quasiperiod 3.

Examples

			In base 3, the RATS mapping acts as 1 -> 2 -> 4 (11 in base 3) -> 8 (22 in base 3) -> 13 (112 in base 3) -> 4, which has already been seen 3 steps ago, so a(3)=3.
		

Crossrefs

Showing 1-4 of 4 results.