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A319811
Number of totally aperiodic integer partitions of n.
1
1, 1, 2, 3, 6, 7, 14, 17, 27, 34, 55, 63, 99, 117, 162, 203, 286, 333, 469, 558, 737, 903, 1196, 1414, 1860, 2232, 2839, 3422, 4359, 5144, 6531, 7762, 9617, 11479, 14182, 16715, 20630, 24333, 29569, 34890, 42335, 49515, 59871, 70042, 83810, 98105, 117152
OFFSET
1,3
COMMENTS
An integer partition is totally aperiodic iff either it is strict or it is aperiodic with totally aperiodic multiplicities.
EXAMPLE
The a(6) = 7 aperiodic integer partitions are: (6), (51), (42), (411), (321), (3111), (21111). The first aperiodic integer partition that is not totally aperiodic is (432211).
MATHEMATICA
totaperQ[m_]:=Or[UnsameQ@@m, And[GCD@@Length/@Split[Sort[m]]==1, totaperQ[Sort[Length/@Split[Sort[m]]]]]];
Table[Length[Select[IntegerPartitions[n], totaperQ]], {n, 30}]
KEYWORD
nonn
AUTHOR
Gus Wiseman, Sep 28 2018
STATUS
approved