In order to generate the next sequence, first take the previous pattern, add the next letter from the alphabet, and then repeat the previous pattern. The first few steps are listed here.6
ABACABA is a "quickly growing word", often described as chiastic or "symmetrically organized around a central axis" (see: Chiastic structure and Χ).7 The number of members in each iteration is a(n) = 2n − 1, the Mersenne numbers (OEIS: A000225).
Naylor, Mike (February 2013). "ABACABA Amazing Pattern, Amazing Connections". Math Horizons. Retrieved June 13, 2019. http://digitaleditions.walsworthprintgroup.com/display_article.php?id=1300604 ↩
SheriOZ (2016-04-21). "Exploring Fractals with ABACABA". Chicago Geek Guy. Archived from the original on 22 January 2021. Retrieved January 22, 2021. https://web.archive.org/web/20210122212731/http://chicagogeekguy.com/exploring-abacaba/ ↩
Naylor, Mike (2011). "Abacaba! – Using a mathematical pattern to connect art, music, poetry and literature" (PDF). Bridges. Retrieved October 6, 2017. http://archive.bridgesmathart.org/2011/bridges2011-89.pdf ↩
Conley, Craig (2008-10-01). Magic Words: A Dictionary. Weiser Books. p. 53. ISBN 9781609250508. 9781609250508 ↩
Halter-Koch, Franz and Tichy, Robert F.; eds. (2000). Algebraic Number Theory and Diophantine Analysis, p.478. W. de Gruyter. ISBN 9783110163049. /wiki/ISBN_(identifier) ↩