तस्य द्विरथोत्तरा वृद्धिरैकविंशतिरथादिति ॥ कZ_१०.५.१५ ॥
tasya dvirathottarā vṛddhir aikaviṃśatirathād iti
Dessa (formação padrão), o incremento faz-se acrescentando dois carros de cada vez — a partir de vinte e um carros.
Even-number increments preserve bilateral symmetry (left/right) and keep wings balanced while scaling the formation.
A minimum viable baseline size for this formation family, from which standardized expansions are authorized.