A138101 The atomic numbers read along the even-indexed rows of the Janet table of the elements.

3, 4, 13, 14, 15, 16, 17, 18, 19, 20, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 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, 119, 120

Offset

1,1

Comments

The union with A138100 gives the first 120 terms of A000027.

Links

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

Albert Tarantola, PSE of Elements (Janet form).

Anonymous, Janet periodic table, Web Elements Chemistry Nexus

Example

Starts with 3 and 4 of the 2nd row (Li and Be). Next come 13 to 20 of the 4th row (Al to Ca).

Mathematica

Table[Range[2 Ceiling[n/2]^2] + (# + 1) (3 + 2 #^2 + 4 # - 3 (-1)^#)/12 &[n - 1], {n, 2, 8, 2}] // Flatten (* Michael De Vlieger, Jul 21 2016 *)

Crossrefs

Cf. A000027, A138100 (odd-indexed rows), A138509 (Left-step Janet periodic table), A137583, A172002.

Sequence in context: A342675 A330158 A082197 * A287089 A095790 A109474

Adjacent sequences: A138098 A138099 A138100 * A138102 A138103 A138104

Keyword

nonn,less,fini,full

Author

Paul Curtz, May 03 2008

Extensions

Edited by R. J. Mathar, Oct 07 2009

Status

approved