A325986 Heinz numbers of complete strict integer partitions.
1, 2, 6, 30, 42, 210, 330, 390, 462, 510, 546, 714, 798, 2310, 2730, 3570, 3990, 4290, 4830, 5610, 6006, 6090, 6270, 6510, 6630, 7410, 7590, 7854, 8778, 8970, 9282, 9570, 9690, 10230, 10374, 10626, 11310, 11730, 12090, 12210, 12558, 13398, 13566, 14322, 14430
Offset: 1
Keywords
Examples
The sequence of terms together with their prime indices begins: 1: {} 2: {1} 6: {1,2} 30: {1,2,3} 42: {1,2,4} 210: {1,2,3,4} 330: {1,2,3,5} 390: {1,2,3,6} 462: {1,2,4,5} 510: {1,2,3,7} 546: {1,2,4,6} 714: {1,2,4,7} 798: {1,2,4,8} 2310: {1,2,3,4,5} 2730: {1,2,3,4,6} 3570: {1,2,3,4,7} 3990: {1,2,3,4,8} 4290: {1,2,3,5,6} 4830: {1,2,3,4,9} 5610: {1,2,3,5,7}
Crossrefs
Programs
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Mathematica
hwt[n_]:=Total[Cases[FactorInteger[n],{p_,k_}:>PrimePi[p] k]]; Select[Range[1000],SquareFreeQ[#]&&Union[hwt/@Divisors[#]]==Range[0,hwt[#]]&]
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