Tā biān dìng de 《 Qián xiàng Lì 》 shì Zhōngguó dìyī bù kǎolǜ yuèqiú jìndìdiǎn yùndòng de lìfǎ.
His Qianxiang Calendar was the first Chinese calendar to account for the moon's perigee motion.
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Liu Hong is also credited in some traditions as an early developer of the abacus (算盘), earning him the nickname 算圣 ('Sage of Calculation'). His lunar-orbit corrections were an advance of nearly a thousand years beyond previous Han calendars.
