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.

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.

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.

A219527 a(n) = (6*n^2 + 7*n - 9 + 2*n^3)/12 - (-1)^n*(n+1)/4.

Original entry on oeis.org

1, 3, 11, 19, 37, 55, 87, 119, 169, 219, 291, 363, 461, 559, 687, 815, 977, 1139, 1339, 1539, 1781, 2023, 2311, 2599, 2937, 3275, 3667, 4059, 4509, 4959, 5471, 5983, 6561, 7139, 7787, 8435, 9157, 9879, 10679, 11479, 12361, 13243
Offset: 1

Views

Author

Paul Curtz, Nov 21 2012

Keywords

Comments

First column of the Mendeleyev-Moseley-Seaborg table (with alkali metals) or 31st column of the Janet table. See A138726.
(a(n+10) - a(n))/10 = 29, 36, 45, 54, ... = A061925(n+7) + 3.
b(n) = a(n+1) - 2*a(n) = 1, 5, -3, -1, -19, -23, -55, -69, -119, -147, -219, -265, -363, -431, ... contains -a(2*n).
b(2*n-1) - b(2*n-2) = 4, 2, -4, -14, -28, -46, -68, ... = A147973(n+3).

Links

Crossrefs

Cf. A147973.

Programs

  • Mathematica
    a[n_] := (6*n^2 + 7*n - 9 + 2*n^3)/12 - (-1)^n*(n + 1)/4; Table[ a[n], {n, 1, 42}] (* Jean-François Alcover, Apr 05 2013 *)
LinearRecurrence[{2,1,-4,1,2,-1},{1,3,11,19,37,55},50] (* Harvey P. Dale, Apr 01 2018 *)

Formula

a(n) = A168380(n+1) - 1.
a(n+2) - a(n+1) = A093907(n) = A137583(n+1).
a(n+3) - a(n+1) = 10,16,26,36,... = A137928(n+3).
G.f. x*(1 + x + 4*x^2 - 2*x^3 + x^5 - x^4) / ( (1+x)^2*(x-1)^4 ). - R. J. Mathar, Mar 27 2013
Showing 1-4 of 4 results.

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