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 1-10 of 13 results. Next

A138724 Atomic numbers of the periodic table of the elements, read downwards along 18 columns, up to the 7th period.

Original entry on oeis.org

1, 3, 11, 19, 37, 55, 87, 4, 12, 20, 38, 56, 88, 21, 39, 57, 89, 22, 40, 72, 104, 23, 41, 73, 105, 24, 42, 74, 106, 25, 43, 75, 107, 26, 44, 76, 108, 27, 45, 77, 109, 28, 46, 78, 110, 29, 47, 79, 111, 30, 48, 80, 112, 5, 13, 31, 49, 81, 113
Offset: 1

Views

Author

Omar E. Pol, Mar 26 2008, Jan 25 2009

Keywords

Comments

This finite sequence has 90 members. Atomic numbers of the elements of Lanthanide series (58 to 71) and Actinide series (90 to 103) and atomic numbers > 118 are not members.

Examples

			=====================================================================
................. THE PERIODIC TABLE OF THE ELEMENTS ................
=====================================================================
1A 2A 3B .4B .5B .6B .7B .8B .8B .8B .1B .2B .3A .4A .5A .6A .7A .8A
=====================================================================
1. .. .. ... ... ... ... ... ... ... ... ... ... ... ... ... ... ..2
3. 4. .. ... ... ... ... ... ... ... ... ... ..5 ..6 ..7 ..8 ..9 .10
11 12 .. ... ... ... ... ... ... ... ... ... .13 .14 .15 .16 .17 .18
19 20 21 .22 .23 .24 .25 .26 .27 .28 .29 .30 .31 .32 .33 .34 .35 .36
37 38 39 .40 .41 .42 .43 .44 .45 .46 .47 .48 .49 .50 .51 .52 .53 .54
55 56 57 .72 .73 .74 .75 .76 .77 .78 .79 .80 .81 .82 .83 .84 .85 .86
87 88 89 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118
=====================================================================

Crossrefs

Cf. A099955, A134984, A138723, A138725, A138726, A138727.

A137575 Successive structures central number of Seaborg's periodic table of the elements (extended to 32 columns) for odd rows.

Original entry on oeis.org

1, 2, 8, 8, 8, 8, 8, 8, 8, 8, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 18, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32
Offset: 1

Views

Author

Paul Curtz, Apr 26 2008

Keywords

Comments

Note that 60 is half of 120, the number of elements in Charles Janet's 32-column table. This implies the existence of element 119, Ununennium (structure last number is 9) and element 120, Unbinilium (10). Structure of element 117, Ununseptium, is unknown.

Crossrefs

Cf. A134984, 118 elements.

Formula

60 terms: 2 (2's) (1,2) + 8 (8's) + 18 (18's) + 32 (32's).

A138723 Atomic numbers of the periodic table of the elements, read downwards along 18 columns, up to the 5th period.

Original entry on oeis.org

1, 3, 11, 19, 37, 4, 12, 20, 38, 21, 39, 22, 40, 23, 41, 24, 42, 25, 43, 26, 44, 27, 45, 28, 46, 29, 47, 30, 48, 5, 13, 31, 49, 6, 14, 32, 50, 7, 15, 33, 51, 8, 16, 34, 52, 9, 17, 35, 53, 2, 10, 18, 36, 54
Offset: 1

Views

Author

Omar E. Pol, Mar 26 2008, Jan 25 2009

Keywords

Comments

This finite sequence has 54 members. Atomic numbers > 54 are not members.

Examples

			===========================================================
........... THE PERIODIC TABLE OF THE ELEMENTS ............
===========================================================
P/G: 1A 2A 3B 4B 5B 6B 7B 8B 8B 8B 1B 2B 3A 4A 5A 6A 7A 8A
===========================================================
(1): .1 .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .2
(2): .3 .4 .. .. .. .. .. .. .. .. .. .. .5 .6 .7 .8 .9 10
(3): 11 12 .. .. .. .. .. .. .. .. .. .. 13 14 15 16 17 18
(4): 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
(5): 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54
===========================================================

Crossrefs

Cf. A099955, A134984, A138724, A138725, A138726, A138727.

A138725 Atomic numbers in the periodic table of the elements, read downwards along 50 columns, up to the 9th period.

Original entry on oeis.org

1, 3, 11, 19, 37, 55, 87, 119, 169, 4, 12, 20, 38, 56, 88, 120, 170, 21, 39, 57, 89, 121, 171, 58, 90, 122, 172, 123, 173, 124, 174, 125, 175, 126, 176, 127, 177, 128, 178, 129, 179, 130, 180, 131, 181, 132, 182, 133, 183, 134, 184
Offset: 1

Views

Author

Omar E. Pol, Mar 26 2008, Jan 25 2009

Keywords

Comments

This finite sequence has 218 members. Atomic numbers > 218 are not members.
This sequence assumes simple extrapolation rather than recent research. - J. Lowell, Jan 26 2021

Examples

			======================================================
................... STRUCTURE OF ....................
........ THE PERIODIC TABLE OF THE ELEMENTS .........
................... (50 columns) ....................
======================================================
1) X................................................X
2) XX..........................................XXXXXX
3) XX..........................................XXXXXX
4) XXX................................XXXXXXXXXXXXXXX
5) XXX................................XXXXXXXXXXXXXXX
6) XXXX..................XXXXXXXXXXXXXXXXXXXXXXXXXXXX
7) XXXX..................XXXXXXXXXXXXXXXXXXXXXXXXXXXX
8) XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
9) XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
======================================================

Crossrefs

Cf. A099955, A134984, A138723, A138724, A138726, A138727.

A138726 Atomic numbers of the periodic table of the elements, read downwards along 72 columns, up to the 11th period.

Original entry on oeis.org

1, 3, 11, 19, 37, 55, 87, 119, 169, 219, 291, 4, 12, 20, 38, 56, 88, 120, 170, 220, 292, 21, 39, 57, 89, 121, 171, 221, 293, 58, 90, 122, 172, 222, 294, 123, 173, 223, 295, 224, 296, 225, 297, 226, 298, 227, 299, 228, 300, 229, 301, 230, 302, 231, 303, 232, 304, 233
Offset: 1

Views

Author

Omar E. Pol, Apr 09 2008

Keywords

Comments

This finite sequence has 362 members. Atomic numbers > 362 are not members.

Examples

			========================================================================
............................ STRUCTURE OF .............................
................. THE PERIODIC TABLE OF THE ELEMENTS ..................
............................ (72 columns) .............................
========================================================================
X......................................................................X
XX................................................................XXXXXX
XX................................................................XXXXXX
XXX......................................................XXXXXXXXXXXXXXX
XXX......................................................XXXXXXXXXXXXXXX
XXXX........................................XXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXX........................................XXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXXX......................XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXXX......................XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
========================================================================

Crossrefs

Cf. A099955, A134984, A138723, A138724, A138725.

A168234 A138100(n) + A168142(n).

Original entry on oeis.org

3, 3, 13, 13, 13, 13, 13, 13, 13, 13, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 39, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 89, 171, 171, 171, 171, 171, 171, 171
Offset: 1

Views

Author

Paul Curtz, Nov 21 2009

Keywords

Comments

A138100 counts upwards in blocks of 2*k^2 numbers, restarting from 1,5,21,57,.. = A166464(k-1) = (2*k+1)*(2*k^2-4*k+3)/3, k>=1.
A168142 counts downwards in blocks of 2*k^2 numbers, restarting from 2*k^2, k>=1.
In consequence, the sequence here contains 2*k^2 copies of the number 1+2*k*(1+2*k^2)/3 = 1+A035597(k), k>=1,
where the sequence A035597 is a bisection of A168380.

Crossrefs

Cf. A134984, A138725, A168208.

Extensions

Edited by R. J. Mathar, Feb 15 2010

A138096 Number of elements in the n-th column of the second extension of the Mendeleyev-Seaborg periodic table of elements.

Original entry on oeis.org

7, 6, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 6, 6, 6, 6, 6, 7
Offset: 1

Views

Author

Paul Curtz, May 03 2008

Keywords

Comments

A variant of A134982, with one term "4" changing place because (relative to the first table) the two elements number 21 and 39 are moved over to the next column of d-metals, placed above element 71.

Crossrefs

Cf. A137583, A093907, A134984, A135559.

A134982 Number of elements in the n-th column of Medeleiev's periodic system of elements.

Original entry on oeis.org

7, 6, 4, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 4, 4, 4, 4, 4, 4, 4, 4, 4, 6, 6, 6, 6, 6, 7
Offset: 1

Views

Author

Paul Curtz, Feb 05 2008

Keywords

Comments

a(1)=7 represents Hydrogen and the alkali metals. Ends with a(32)=7 for 7 noble gases. These are the block counts (grouping) of the atomic numbers A134984. - R. J. Mathar, Feb 08 2008
The corresponding row numbers are A093907; the sum over all a(n) equals 118 in both cases. - R. J. Mathar, Feb 08 2008
Comment from Paul Curtz, May 03 2008 (Start):
1................................................................................................................2
3..4.........................................................................................5...6...7...8...9..10
11.12.......................................................................................13..14..15..16..17..18
19.20.21................................................22..23..24..25..26..27..28..29..30..31..32..33..34..35..36
37.38.39................................................40..41..42..43..44..45..46..47..48..49..50..51..52..53..54
55.56.57.58.59.60.61.62.63.64.65.66.67..68..69..70..71..72..73..74..75..76..77..78..79..80..81..82..83..84..85..86
87.88.89.90.91.92.93.94.95.96.97.98.99.100.101.102.103.104.105.106.107.108.109.110.111.112.113.114.115.116.117.118
(End)

Crossrefs

Cf. A134984, A093907, A137583, A135559.

Extensions

Edited by R. J. Mathar, Feb 08 2008

A137904 Rows 1, 3, 5, 7 of Mendeleyev-Seaborg (extended to 32 columns) periodic table elements.

Original entry on oeis.org

1, 2, 11, 12, 13, 14, 15, 16, 17, 18, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118
Offset: 0

Views

Author

Paul Curtz, Apr 30 2008

Keywords

Comments

60 terms. See A137575 (58 terms for rows 2, 4, 6). Differences 9, 19, 33 leads to difference 3 before a(1)=1. Hence -2, antihelium. Like A137583, 2, 2, 8 for A018227, 2, 10, 18, "magic numbers".

References

  • R. Arsenescu, Antihelium-3 production in lead-lead collisions at 158 A GeV/c. New Journal of Physics 5:1,2003. doi:10.1088/1367-2630/5/1/301.

Crossrefs

Cf. A134984, A137913.

A137913 Rows 2, 4, 6 of Mendeleyev-Seaborg (extended to 32 columns) periodic table elements.

Original entry on oeis.org

3, 4, 5, 6, 7, 8, 9, 10, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86
Offset: 0

Views

Author

Paul Curtz, Apr 30 2008

Keywords

Comments

58 terms. Companion of A137904(60 terms). Both "well" ordered give 118 terms sequence (increasing) 1 to 118;19-10=9, 55-36=19, a(n) differences lead to difference 3 before a(0)=3. Hence neutral element 0.

Crossrefs

Cf. A134984, A135559.
Showing 1-10 of 13 results. Next

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