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 A339628 Number of compositions (ordered partitions) of n into distinct parts such that the sum of reciprocals of parts is an integer. 2
 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 6, 24, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 24, 120, 0, 0, 0, 0, 24, 144, 144, 120, 0, 0, 0, 24, 240, 720, 0, 0, 0, 120, 720, 240, 1440, 0, 0, 0, 840, 5760, 720, 5160, 744, 240, 720, 1440, 10080, 720, 5760, 5160, 1560, 5760, 2280, 16560, 6000, 7560 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,12 COMMENTS Also the number of ordered ways to express an integer as the sum of distinct unit fractions such that the sum of the denominators is n. LINKS EXAMPLE a(11) = 6 because we have 2 + 3 + 6 = 2 + 6 + 3 = 3 + 2 + 6 = 3 + 6 + 2 = 6 + 2 + 3 = 6 + 3 + 2 = 11 and 1/2 + 1/3 + 1/6 = 1 is an integer. CROSSREFS Cf. A051907, A051908, A058360, A339627, A339629. Sequence in context: A013266 A154420 A255305 * A304271 A293590 A194770 Adjacent sequences:  A339625 A339626 A339627 * A339629 A339630 A339631 KEYWORD nonn AUTHOR Ilya Gutkovskiy, Dec 10 2020 STATUS approved

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Last modified May 26 17:16 EDT 2022. Contains 354092 sequences. (Running on oeis4.)