3 ms·
Made me think of the Trachtenberg Speed System: http://mathforum.org/dr.math/faq/faq.trachten.html http://mathforum.org/dr.math/faq/faq.trachten.html
by nikatwork 14y ago
Made me think of the Trachtenberg Speed System:
http://mathforum.org/dr.math/faq/faq.trachten.html http://mathforum.org/dr.math/faq/faq.trachten.html