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A325618
Numbers m such that there exists an integer partition of m whose reciprocal factorial sum is 1.
11
1, 4, 11, 18, 24, 31, 37, 44, 45, 50, 52, 57, 58, 65, 66, 70, 71, 73, 76, 78, 79, 83, 86, 87, 89, 91, 92, 94, 96, 97, 99, 100, 102, 104, 107, 108, 109, 110, 112, 113, 114, 115, 117, 118, 119, 120, 121, 122, 123, 125, 126, 127, 128, 130, 131
OFFSET
1,2
COMMENTS
The reciprocal factorial sum of an integer partition (y_1,...,y_k) is 1/y_1! + ... + 1/y_k!.
Conjecture: 137 is the greatest integer not in this sequence. - Charlie Neder, May 14 2019
LINKS
EXAMPLE
The sequence of terms together with an integer partition of each whose reciprocal factorial sum is 1 begins:
1: (1)
4: (2,2)
11: (3,3,3,2)
18: (3,3,3,3,3,3)
24: (4,4,4,4,3,3,2)
31: (4,4,4,4,3,3,3,3,3)
37: (4,4,4,4,4,4,4,4,3,2)
44: (4,4,4,4,4,4,4,4,3,3,3,3)
45: (5,5,5,5,5,4,4,4,3,3,2)
50: (4,4,4,4,4,4,4,4,4,4,4,4,2)
CROSSREFS
KEYWORD
nonn
AUTHOR
Gus Wiseman, May 13 2019
EXTENSIONS
a(11)-a(55) from Charlie Neder, May 14 2019
STATUS
approved