A168342 Even atomic numbers in the Janet table of the PSE, read right to left along rows.

2, 4, 12, 10, 8, 6, 20, 18, 16, 14, 38, 36, 34, 32, 30, 28, 26, 24, 22, 56, 54, 52, 50, 48, 46, 44, 42, 40, 88, 86, 84, 82, 80, 78, 76, 74, 72, 70, 68, 66, 64, 62, 60, 58, 120, 118, 116, 114, 112, 110, 108, 106, 104, 102, 100, 98, 96, 94, 92, 90

Offset

1,1

Comments

In the Janet arrangement, the elements appear in groups of twice 2, twice 8,... twice 2*k^2, and are here right-aligned:

...............................1,.2;

...............................3,.4;

.............5,.6,.7,.8,.9,10,11,12;

............13,14,15,16,17,18,19,20;

...28,39.30,31,32,33,34,35,36,37,38;

The even numbers in the table are read top-down, right-to-left and entered into the sequence (which, in consequence, is a permutation of the even numbers.)

Links

Table of n, a(n) for n=1..60.

A. Tarantola, Periodic table of elements (Janet form)

Example

Skipping each second (i.e., each odd) element in the table, the result is
2;
4;
12,10,8,6;
20,18,16,14;
38,36,34,32,30,28,..
counting down the even numbers restarting at indices provided by A168380.

Crossrefs

Cf. A138100, A138101, A168142.

Sequence in context: A181817 A362227 A000348 * A309515 A375551 A342311

Adjacent sequences: A168339 A168340 A168341 * A168343 A168344 A168345

Keyword

nonn,less,tabf

Author

Paul Curtz, Nov 23 2009

Status

approved