login
A038587
Sizes of successive clusters in hexagonal lattice A_2 centered at deep hole.
2
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.
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
KEYWORD
nonn
STATUS
approved