OFFSET
0,1
COMMENTS
The Heinz number of a set of positive integers {y_1,...,y_k} is prime(y_1)*...*prime(y_k).
All terms are squarefree and pairwise relatively prime.
FORMULA
EXAMPLE
The integer partitions of 3 are {(3), (2,1), (1,1,1)}, with Heinz numbers {5,6,8}, with Heinz number prime(5)*prime(6)*prime(8) = 2717, so a(3) = 2717.
The sequence of terms together with their prime indices begins:
2: {1}
3: {2}
35: {3,4}
2717: {5,6,8}
22235779: {7,9,10,12,16}
3163570326979: {11,14,15,18,20,24,32}
51747966790650260753033: {13,21,22,25,27,28,30,36,40,48,64}
MATHEMATICA
Table[Times@@Prime/@(Times@@Prime/@#&/@IntegerPartitions[n]), {n, 0, 5}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Gus Wiseman, May 05 2019
STATUS
approved