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 A325622 Number of integer partitions of n whose reciprocal factorial sum is the reciprocal of an integer. 7
 1, 1, 1, 2, 1, 2, 1, 2, 3, 2, 3, 3, 2, 2, 3, 3, 3, 5, 4, 4, 3, 3, 4, 6, 3, 4, 5, 5, 5, 6, 3, 7, 6, 5, 6, 6, 6, 5, 6, 8, 5, 7, 5, 4, 8, 7, 7, 7, 7, 9, 9, 9, 10, 12, 6, 12, 8, 10, 7, 14 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS The reciprocal factorial sum of an integer partition (y_1,...,y_k) is 1/y_1! + ... + 1/y_k!. LINKS EXAMPLE The initial terms count the following partitions:    1: (1)    2: (2)    3: (3)    4: (4)    4: (2,2)    5: (5)    6: (6)    6: (3,3)    7: (7)    8: (8)    8: (4,4)    9: (9)    9: (5,4)    9: (3,3,3)   10: (10)   10: (5,5)   11: (11)   11: (4,4,3)   11: (3,3,3,2)   12: (12)   12: (6,6)   12: (4,4,4) MATHEMATICA Table[Length[Select[IntegerPartitions[n], IntegerQ[1/Total[1/(#!)]]&]], {n, 30}] CROSSREFS Factorial numbers: A000142, A007489, A022559, A064986, A108731, A115944, A284605, A325508, A325616. Reciprocal factorial sum: A002966, A316854, A316857, A325618, A325620, A325623. Sequence in context: A194509 A054716 A261641 * A060145 A257806 A035391 Adjacent sequences:  A325619 A325620 A325621 * A325623 A325624 A325625 KEYWORD nonn,more AUTHOR Gus Wiseman, May 13 2019 STATUS approved

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Last modified April 17 01:37 EDT 2021. Contains 343051 sequences. (Running on oeis4.)