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This is a highly detailed regex pattern that validates Chinese mobile phone number prefixes. It matches specific digit combinations after the leading '1' in Chinese mobile numbers (13x, 14x, 15x, 17x, 18x, 19x series), covering all valid carrier-assigned number ranges for China Mobile, China Unicom, China Telecom, and MVNOs. The pattern accounts for newly allocated number segments and MVNO (170/171) prefixes.