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A325233 Heinz numbers of integer partitions with Dyson rank 1. 15
3, 10, 15, 25, 28, 42, 63, 70, 88, 98, 105, 132, 147, 175, 198, 208, 220, 245, 297, 308, 312, 330, 343, 462, 468, 484, 495, 520, 544, 550, 693, 702, 726, 728, 770, 780, 816, 825, 1053, 1078, 1089, 1092, 1144, 1155, 1170, 1210, 1216, 1224, 1300, 1352, 1360 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Numbers whose maximum prime index is one greater than their number of prime indices counted with multiplicity.
The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k).
LINKS
EXAMPLE
The sequence of terms together with their prime indices begins:
3: {2}
10: {1,3}
15: {2,3}
25: {3,3}
28: {1,1,4}
42: {1,2,4}
63: {2,2,4}
70: {1,3,4}
88: {1,1,1,5}
98: {1,4,4}
105: {2,3,4}
132: {1,1,2,5}
147: {2,4,4}
175: {3,3,4}
198: {1,2,2,5}
208: {1,1,1,1,6}
220: {1,1,3,5}
245: {3,4,4}
297: {2,2,2,5}
308: {1,1,4,5}
MATHEMATICA
Select[Range[1000], PrimePi[FactorInteger[#][[-1, 1]]]-PrimeOmega[#]==1&]
CROSSREFS
Positions of 1's in A257541.
Sequence in context: A247420 A063231 A224852 * A030005 A192163 A129307
KEYWORD
nonn
AUTHOR
Gus Wiseman, Apr 13 2019
STATUS
approved

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Last modified April 24 14:54 EDT 2024. Contains 371960 sequences. (Running on oeis4.)