{'fraction_non_alphanumeric': 0.013574660633484163, 'fraction_numerical': 0.0, 'mean_word_length': 4.906666666666666, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Eccentric Connectivity Index of Chemical Trees

The eccentric connectivity index ξc is a distance-based molecular structure descriptor that was recently used for mathematical modeling of biological activities of diverse nature. We prove that the broom has maximum ξ c among trees with a fixed maximum vertex degree, and characterize such trees with minimum ξ c . In addition, we propose a simple linear algorithm for calculating ξ c of trees.