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A339627
Number of 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, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 2, 2, 1, 0, 0, 0, 1, 2, 1, 0, 0, 0, 1, 1, 2, 2, 0, 0, 0, 2, 2, 1, 2, 2, 2, 1, 2, 2, 1, 2, 2, 3, 2, 4, 5, 4, 7, 4, 2, 2, 6, 6, 1, 3, 3, 4, 3, 4
OFFSET
0,32
COMMENTS
Also the number of ways to express an integer as the sum of distinct unit fractions such that the sum of the denominators is n.
EXAMPLE
a(31) = 2 because we have 2 + 4 + 5 + 20 = 1 + 2 + 3 + 10 + 15 = 31 and 1/2 + 1/4 + 1/5 + 1/20 = 1, 1/1 + 1/2 + 1/3 + 1/10 + 1/15 = 2 are integers.
CROSSREFS
KEYWORD
nonn
AUTHOR
Ilya Gutkovskiy, Dec 10 2020
STATUS
approved