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A318584
Number of integer partitions of n whose sum of reciprocals squared is 1.
5
0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 1, 0, 2, 2, 0, 0, 0, 2, 0, 2, 1, 2, 2, 2, 1, 1, 2, 3, 0, 1, 1, 6, 2, 3, 2, 6, 2, 2, 3, 2, 6, 7, 2, 4, 3, 9, 4, 7, 5, 8, 8, 7, 9, 9, 11, 12, 7, 9, 11, 17, 9, 13, 12, 17, 16, 13, 15, 20, 26, 27, 18, 23
OFFSET
0,42
COMMENTS
The a(16) = 1 integer partition:
(6,3,3,2,2,2)
The a(48) = 2 integer partitions:
(18,9,9,3,3,2,2,2)
(6,6,6,6,3,3,3,3,3,3,3,3)
The a(56) = 3 integer partitions:
(12,6,6,4,4,4,4,4,4,4,2,2)
(10,6,5,5,5,5,5,5,3,3,2,2)
(6,6,4,4,4,4,4,4,4,4,3,3,3,3)
The a(60) = 6 integer partitions:
(12,12,12,12,3,3,2,2,2)
(8,8,8,8,6,4,4,4,3,3,2,2)
(6,6,6,6,6,6,6,6,6,2,2,2)
(12,12,12,4,3,3,3,3,3,3,2)
(10,5,5,5,5,5,5,4,4,4,4,2,2)
(6,4,4,4,4,4,4,4,4,4,4,4,4,3,3)
MATHEMATICA
Table[Length[Select[IntegerPartitions[n], Total[#^(-2)]==1&]], {n, 30}]
KEYWORD
nonn
AUTHOR
Gus Wiseman, Aug 29 2018
EXTENSIONS
a(61)-a(100) from Alois P. Heinz, Aug 30 2018
STATUS
approved