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A319333 Heinz numbers of integer partitions whose sum is equal to their LCM. 8

%I #6 Sep 19 2018 09:17:22

%S 2,3,5,7,11,13,17,19,23,29,30,31,37,41,43,47,53,59,61,67,71,73,79,83,

%T 89,97,101,103,107,109,113,127,131,137,139,149,151,157,163,167,173,

%U 179,181,191,193,197,198,199,211,223,227,229,233,239,241,251,257,263

%N Heinz numbers of integer partitions whose sum is equal to their LCM.

%C The Heinz number of an integer partition (y_1, ..., y_k) is prime(y_1) * ... * prime(y_k).

%e The sequence of partitions whose Heinz numbers are in the sequence begins: (1), (2), (3), (4), (5), (6), (7), (8), (9), (10), (3,2,1), (11), (12).

%t primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];

%t Select[Range[2,100],LCM@@primeMS[#]==Total[primeMS[#]]&]

%Y Cf. A067538, A074761, A143773, A290103, A305566, A316429, A316431, A316432, A316433, A317624, A319315, A319334.

%K nonn

%O 1,1

%A _Gus Wiseman_, Sep 17 2018

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