No. atoms in colloid

Hello,
How the number of atoms are calculated in colloid example? In the output, I see

Lattice spacing in x,y,z = 10 10 10
Created orthogonal box = (0 0 -5) to (20000 300 5)
  1 by 1 by 1 MPI processor grid
Created 60000 atoms

In the input file, I can not figure out how that is calculated.

# Big colloid particles and small LJ particles
units		lj
atom_style	sphere
dimension	2

lattice		sq 0.01
region		box block 0 2000 0 30 -0.5 0.5
create_box	2 box
create_atoms	1 box

set		group all type/fraction 2 0.96 23984
set		type 1 mass 9
set		type 2 mass 1

velocity	all create 1.44 87287 loop geom
# multi neighbor and comm for efficiency
neighbor	1 multi
neigh_modify	delay 0
comm_modify     mode multi

# colloid potential
pair_style	colloid 12.5
pair_coeff	1 1  1.0 1.0 5.0 5.0 12.5
pair_coeff	1 2  5.0 1.0 5.0 0.0 7.0
pair_coeff	2 2 10.0 1.0 0.0 0.0 2.5

fix		1 all npt temp 2.0 2.0 1.0 iso 0.0 1.0 10.0 drag 1.0 &
	        mtk no pchain 0 tchain 1
fix		2 all enforce2d
thermo_style	custom step temp epair etotal press vol
thermo		200
timestep	0.005
run	        2000

I read the manual page, but still it’s not clear yet. Any thoughts on that?

Please check out the documentation for these five commands. Its is the combination of all five that determines the number of atoms. All the information you need is in the LAMMPS manual is is merely a matter to notice all the details and cross-links. The pair style has no impact on this.

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