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A325706 Heinz numbers of integer partitions containing all of their distinct multiplicities. 7
1, 2, 6, 9, 10, 12, 14, 18, 22, 26, 30, 34, 36, 38, 40, 42, 46, 58, 60, 62, 66, 70, 74, 78, 82, 84, 86, 90, 94, 102, 106, 110, 112, 114, 118, 120, 122, 125, 126, 130, 132, 134, 138, 142, 146, 150, 154, 156, 158, 166, 170, 174, 178, 180, 182, 186, 190, 194, 198 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k).
Also numbers n divisible by the squarefree kernel of their "shadow" A181819(n).
The enumeration of these partitions by sum is given by A325705.
LINKS
EXAMPLE
The sequence of terms together with their prime indices begins:
1: {}
2: {1}
6: {1,2}
9: {2,2}
10: {1,3}
12: {1,1,2}
14: {1,4}
18: {1,2,2}
22: {1,5}
26: {1,6}
30: {1,2,3}
34: {1,7}
36: {1,1,2,2}
38: {1,8}
40: {1,1,1,3}
42: {1,2,4}
46: {1,9}
58: {1,10}
60: {1,1,2,3}
62: {1,11}
MATHEMATICA
Select[Range[100], #==1||SubsetQ[PrimePi/@First/@FactorInteger[#], Last/@FactorInteger[#]]&]
CROSSREFS
Sequence in context: A121248 A268677 A108370 * A367683 A325185 A285532
KEYWORD
nonn
AUTHOR
Gus Wiseman, May 18 2019
STATUS
approved

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Last modified April 19 05:02 EDT 2024. Contains 371782 sequences. (Running on oeis4.)