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.

Previous Showing 11-17 of 17 results.

A194435 Number of toothpicks or D-toothpicks added at n-th stage to the structure of A194434.

Original entry on oeis.org

0, 4, 8, 16, 16, 16, 32, 44, 32, 16, 32, 64, 96, 48, 80, 100, 64, 16, 32, 64, 96, 112, 144, 168, 176, 80, 96, 160, 256, 128, 176, 212, 128, 16, 32, 64, 96, 112, 144, 176, 208, 168, 192, 240, 400, 272, 336, 332, 336, 112, 96, 176, 288, 336, 416, 464
Offset: 0

Views

Author

Omar E. Pol, Sep 03 2011

Keywords

Comments

Essentially the first differences of A194434.
First differs from A221528 at a(13). - Omar E. Pol, Mar 23 2013
From Omar E. Pol, Jun 24 2022: (Start)
The word of this cellular automaton is "ab".
For the nonzero terms the structure of the irregular triangle is as shown below:
a,b;
a,b;
a,b,a,b;
a,b,a,b,a,b,a,b;
a,b,a,b,a,b,a,b,a,b,a,b,a,b,a,b;
...
Row lengths are the terms of A011782 multiplied by 2, also the column 2 of A296612.
Columns "a" contain numbers of D-toothpicks (of length sqrt(2)).
Columns "b" contain numbers of toothpicks (of length 1).
An associated sound to the animation could be (tick, tock), (tick, tock), ..., the same as the ticking clock sound.
For further information about the word of cellular automata see A296612. (End)

Examples

			From _Omar E. Pol_, Mar 23 2013: (Start)
When written as an irregular triangle the sequence of nonzeros terms begins:
   4, 8;
  16,16;
  16,32,44,32;
  16,32,64,96, 48, 80,100, 64;
  16,32,64,96,112,144,168,176, 80, 96,160,256,128,176,212,128;
  16,32,64,96,112,144,176,208,168,192,240,400,272,336,332,336,112,96, ...
  ... (End)
Right border gives the powers of 2 >= 8 (reformatted the triangle). - _Omar E. Pol_, Jun 24 2022
		

Crossrefs

Formula

a(n) = 4*A194445(n).
Conjecture: a(2^k+1) = 16, if k >= 1.

Extensions

More terms from Omar E. Pol, Mar 23 2013

A194693 Number of toothpicks or D-toothpicks added at n-th stage to the D-toothpick "corner" structure of A194692.

Original entry on oeis.org

2, 2, 4, 6, 8, 8, 12, 13, 12, 10, 16, 20, 32, 20, 24, 27, 20, 10, 16, 24, 36, 41, 48, 48, 54, 34, 44, 50, 80, 48, 48, 55, 36, 10, 16, 24, 36, 41, 48, 54, 68, 62, 80, 80, 124, 95, 104, 89, 94, 44, 48, 68
Offset: 1

Views

Author

Omar E. Pol, Sep 03 2011

Keywords

Comments

Sequence related to the D-toothpick "wide" triangle (See A194440 and A194441). First differences of A194692.

Examples

			Written as a triangle:
2,
2,
4,
6,8,
8,12,13,12,
10,16,20,32,20,24,27,20,
10,16,24,36,41,48,48,54,34,44,50,80,48,48,55,36,
10,16,24,36,41,48,54,68,62,80,80,124,95,104,89,94,44,...
		

Crossrefs

Formula

a(n) = A194696(n)/2.
Conjectures for n = 2^k+j, if 0<=j<=3:
a(2^k) = 7*2^(k-2)-1, if k >= 2.
a(2^k+1) = 2^k+4, if k >= 2.
a(2^k+2) = 10, if k >= 3.
a(2^k+3) = 16, if k >= 3.
End conjectures.

A194696 a(n) = 2*A194693(n).

Original entry on oeis.org

4, 4, 8, 12, 16, 16, 24, 26, 24, 20, 32, 40, 64, 40, 48, 54, 40, 20, 32, 48, 72, 82, 96, 96, 108, 68, 88, 100, 160, 96, 96, 110, 72, 20, 32, 48, 72, 82, 96, 108, 136, 124, 160, 160, 248, 190, 208, 178, 188, 88, 96, 136
Offset: 1

Views

Author

Omar E. Pol, Sep 03 2011

Keywords

Comments

Conjecture: number of toothpicks or D-toothpicks added to the structure of A194440 at stage 2^k+n, if k tends to infinity. It appears that rows of A194441 when written as a triangle converge to this sequence.

Examples

			Written as a triangle:
4,
4,
8,
12,16,
16,24,26,24,
20,32,40,64,40,48,54,40,
20,32,48,72,82,96,96,108,68,88,100,160,96,96,110,72,
20,32,48,72,82,96,108,136,124,160,160,248,190,208,178,...
		

Crossrefs

A220527 Number of toothpicks or D-toothpicks added at n-th stage in the toothpick structure of A220526.

Original entry on oeis.org

0, 1, 2, 4, 4, 4, 4, 7, 8, 4, 4, 8, 12, 14, 12, 15, 16, 4, 4, 8, 12, 16, 10, 24, 26
Offset: 0

Views

Author

Omar E. Pol, Jan 02 2013

Keywords

Comments

Essentially the first differences of A220526.

Examples

			Written as an irregular triangle begins:
0;
1;
2;
4,4;
4,4,7,8;
4,4,8,12,14,12,15,16;
4,4,8,12,16,10,24,26,...
		

Crossrefs

A212009 Number of toothpicks or D-toothpicks added at n-th stage in the toothpick structure of A212008.

Original entry on oeis.org

0, 1, 4, 8, 16, 22, 20, 24, 36, 40, 32, 44, 56, 94, 60, 56, 76, 72, 32, 48, 72, 112, 132, 140, 136, 168, 112, 132, 140, 238, 148, 120, 156, 136, 32, 48, 72, 112, 132
Offset: 0

Views

Author

Omar E. Pol, Dec 15 2012

Keywords

Comments

Essentially the first differences of A212008.

Examples

			When written as an irregular triangle:
0;
1;
4;
8;
16,22;
20,24,36,40;
32,44,56,94,60,56,76,72;
32,48,72,112,132,140,136,168,112,132,140,238,148,120,156,136;
32,48,72,112,132,...
		

Crossrefs

Formula

It appears that a(2^k + 2) = 32, if k >= 3.

A220495 Number of toothpicks or D-toothpicks added at n-th stage to the structure of A220494.

Original entry on oeis.org

0, 1, 2, 4, 4, 4, 4, 8, 8, 4, 4, 8, 8, 8, 8, 16, 16, 4, 4, 8, 8, 8, 8, 16, 16, 8, 8, 16, 16, 16, 16, 32, 32, 4, 4, 8, 8, 8, 8, 16, 16, 8, 8, 16, 16, 16, 16, 32, 32, 8, 8, 16, 16, 16, 16, 32, 32, 16, 16, 32, 32, 32, 32, 64, 64, 4, 4, 8, 8, 8, 8, 16, 16
Offset: 0

Views

Author

Omar E. Pol, Dec 23 2012

Keywords

Comments

Essentially the first differences of A220494.
First differs from A194441 (and from A220521) at a(12).

Examples

			When written as an irregular triangle begins:
0;
1;
2;
4,4;
4,4,8,8;
4,4,8,8,8,8,16,16;
4,4,8,8,8,8,16,16,8,8,16,16,16,16,32,32;
4,4,8,8,8,8,16,16,8,8,16,16,16,16,32,32,8,8,16,16,...
		

Crossrefs

A233777 Number of vertices in the n-th row of the toothpick structure of A233776, with a(0) = 1.

Original entry on oeis.org

1, 1, 2, 2, 3, 2, 4, 4, 5, 2, 4, 4, 6, 4, 8, 8, 9, 2, 4, 4, 6, 4, 8, 8, 10, 4, 8, 8, 12, 8, 16, 16, 17, 2, 4, 4, 6, 4, 8, 8, 10, 4, 8, 8, 12, 8, 16, 16, 18, 4, 8, 8, 12, 8, 16, 16, 20, 8, 16, 16, 24, 16, 32, 32, 33, 2, 4, 4, 6, 4, 8, 8, 10, 4, 8, 8, 12
Offset: 0

Views

Author

Omar E. Pol, Dec 25 2013

Keywords

Examples

			Illustration of initial terms:
---------------------------------------------------------
. A001316 A006046         Diagram          a(n)  A233776
---------------------------------------------------------
.            0
.                            *               1       1
.    1       1               |
.                            *               1       2
.    2       3              / \
.                          *   *             2       4
.    2       5             |   |
.                          *   *             2       6
.    4       9            / \ / \
.                        *   *   *           3       9
.    2      11           |       |
.                        *       *           2      11
.    4      15          / \     / \
.                      *   *   *   *         4      15
.    4      19         |   |   |   |
.                      *   *   *   *         4      19
.    8      27        / \ / \ / \ / \
.                    *   *   *   *   *       5      24
.    2      29       |               |
.                    *               *       2      26
.    4      33      / \             / \
.                  *   *           *   *     4      30
.
Written as an irregular triangle the sequence begins:
1;
1;
2;
2,3;
2,4,4,5;
2,4,4,6,4,8,8,9;
2,4,4,6,4,8,8,10,4,8,8,12,8,16,16,17;
2,4,4,6,4,8,8,10,4,8,8,12,8,16,16,18,4,8,8,12,8,16,16,20,8,16,16,24,16,32,32,33;
		

Crossrefs

Previous Showing 11-17 of 17 results.