Usage: 4 forms in 4 verses
Form Translated As     In Verse(s)
εκτεταγμένων being arrayed LXX.Neh.4.16
εκτεταγμένοι being arrayed LXX.Num.32.27
εκτάσσοντα arraying LXX.2Kgs.25.19
εκτάξαντα arraying LXX.Dan.1.10

Liddell-Scott-Jones

ἐκτάσσω (ektassō) to array G:V

ἐκτάσσω,

Attic dialect ἐκτάττω, draw out in battle-order, of the officers, [Refs 2nd c.BC+]:—middle, draw themselves out, of the soldiers, [Refs 5th c.BC+]:—passive, [Refs 2nd c.BC+]

__II keep muster-roll of, λαόν [LXX]
__II.2 ἐκτάσσοντα· χαράσσοντα, γράφοντα, [Refs 5th c.AD+]

LSJ Scripture Refs: LXX.2Kgs.25.19