俱舍論頌疏論本 28.72

28.72

至間超為成者，明修超也。謂觀行者修超定時，先於有漏八地等至順逆均次現前數習，次於無漏七地等至順逆均次現前數習，次於有漏無漏等至順逆間次現前數習，次於有漏順逆均超現前數習，次於無漏順逆均超現前數習，是名修習超加行成滿。後於有漏無漏等至順逆間超，名超定成。

As for 'reaching the skipped alternating marks accomplishment,' this explains the cultivation of skipping. When a meditator cultivates the skipping absorption, first, regarding the defiled samāpattis of the eight stages, one repeatedly practices them manifesting in direct and reverse order, uniformly and successively; next, regarding the undefiled samāpattis of the seven stages, one repeatedly practices them manifesting in direct and reverse order, uniformly and successively; next, regarding the defiled and undefiled samāpattis, one repeatedly practices them manifesting in direct and reverse order, alternatingly and successively; next, regarding the defiled, one repeatedly practices them manifesting in direct and reverse order, uniformly and skippingly; next, regarding the undefiled, one repeatedly practices them manifesting in direct and reverse order, uniformly and skippingly: this is called the completion of the preparatory cultivation of skipping. Afterward, regarding the defiled and undefiled samāpattis, manifesting in direct and reverse order, alternatingly and skippingly, is called the accomplishment of the skipping absorption.