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.

A130556 A model of the atomic nucleus (Shell model of nucleus). A triangle.

Original entry on oeis.org

1, 11, 1, 111, 1, 11, 1111, 11, 1, 111, 11111, 111, 1, 11, 1111, 111111, 1111, 11, 1, 111, 11111, 1111111, 11111, 111, 1, 11, 1111, 111111, 11111111, 111111, 1111, 11, 1, 111, 11111, 1111111
Offset: 1

Views

Author

Omar E. Pol, Aug 09 2007, Aug 12 2007

Keywords

Comments

1 is equal to 2 protons, 11 is equal to 2+2 protons, 111 is equal to 2+2+2 protons...
Repunit numbers represent the subshells.

Examples

			A geometric model of the shell structure of nucleus:
...|----------------------.i.----------------------|
...|...|------------------.h.------------------|...|
...|...|...|--------------.g.--------------|...|...|
...|...|...|...|----------.f.----------|...|...|...|
...|...|...|...|...|------.d.------|...|...|...|...|
...|...|...|...|...|...|--.p.--|...|...|...|...|...|
...|...|...|...|...|...|...s...|...|...|...|...|...|
...|...|...|...|...|...|...|...|...|...|...|...|...|
...|...|...|...|...|...|.......|...|...|...|...|...|
...|...|...|...|...|.......1.......|...|...|...|...|
...|...|...|...|......11.......1.......|...|...|...|
...|...|...|......111......1......11.......|...|...|
...|...|.....1111.....11.......1......111......|...|
...|.....11111....111......1......11.....1111......|
....111111...1111.....11.......1......111....11111....
1111111..11111....111......1......11.....1111...111111
......................................................
...|...|...|...|...|...|...|...|...|...|...|...|...|
...|...|...|...|...|...|...|1/2|...|...|...|...|...|
...|...|...|...|...|...|----3/2----|...|...|...|...|
...|...|...|...|...|--------5/2--------|...|...|...|
...|...|...|...|------------7/2------------|...|...|
...|...|...|----------------9/2----------------|...|
...|...|-------------------11/2--------------------|
...|----------------------.13/2.--------------------
		

Crossrefs