A038587 Sizes of successive clusters in hexagonal lattice A_2 centered at deep hole.

3, 6, 12, 12, 18, 21, 27, 27, 30, 36, 42, 42, 48, 48, 54, 54, 63, 69, 69, 69, 75, 78, 84, 84, 90, 96, 102, 102, 102, 102, 114, 114, 120, 123, 129, 129, 135, 141, 141, 141, 144, 150, 156, 156, 168, 168, 174, 174, 174

Offset

0,1

Comments

The hexagonal lattice is the familiar 2-dimensional lattice in which each point has 6 neighbors. This is sometimes called the triangular lattice.

Links

Table of n, a(n) for n=0..48.

G. Nebe and N. J. A. Sloane, Home page for hexagonal (or triangular) lattice A2

Mathematica

CoefficientList[3 QPochhammer[q^3]^3 / QPochhammer[q] + O[q]^50, q] // Accumulate (* Jean-François Alcover, Jul 05 2019 *)

Crossrefs

Partial sums of A005882.

Cf. A038588.

Sequence in context: A254793 A353715 A182633 * A090553 A078502 A107974

Adjacent sequences: A038584 A038585 A038586 * A038588 A038589 A038590

Keyword

nonn

Author

N. J. A. Sloane.

Status

approved