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A325762
Heinz numbers of integer partitions with no part greater than the number of ones.
3
1, 2, 4, 8, 12, 16, 24, 32, 36, 40, 48, 64, 72, 80, 96, 108, 112, 120, 128, 144, 160, 192, 200, 216, 224, 240, 256, 288, 320, 324, 336, 352, 360, 384, 400, 432, 448, 480, 512, 560, 576, 600, 640, 648, 672, 704, 720, 768, 784, 800, 832, 864, 896, 960, 972, 1000
OFFSET
1,2
COMMENTS
After 1 and 2, first differs from A322136 in having 200.
The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k).
The enumeration of these partitions by sum is given by A002865.
EXAMPLE
The sequence of terms together with their prime indices begins:
1: {}
2: {1}
4: {1,1}
8: {1,1,1}
12: {1,1,2}
16: {1,1,1,1}
24: {1,1,1,2}
32: {1,1,1,1,1}
36: {1,1,2,2}
40: {1,1,1,3}
48: {1,1,1,1,2}
64: {1,1,1,1,1,1}
72: {1,1,1,2,2}
80: {1,1,1,1,3}
96: {1,1,1,1,1,2}
108: {1,1,2,2,2}
112: {1,1,1,1,4}
120: {1,1,1,2,3}
128: {1,1,1,1,1,1,1}
144: {1,1,1,1,2,2}
MATHEMATICA
Select[Range[100], #==1||EvenQ[#]&&PrimePi[FactorInteger[#][[-1, 1]]]<=FactorInteger[#][[1, 2]]&]
KEYWORD
nonn
AUTHOR
Gus Wiseman, May 18 2019
STATUS
approved