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A326848 Heinz numbers of integer partitions of m >= 0 whose length times maximum is a multiple of m. 12

%I #5 Jul 29 2019 13:55:37

%S 1,2,3,4,5,7,8,9,11,13,16,17,19,23,25,27,28,29,31,32,37,40,41,43,47,

%T 49,53,59,61,64,67,71,73,78,79,81,83,84,89,97,101,103,107,109,113,121,

%U 125,127,128,131,137,139,149,151,157,163,167,169,171,173,179,181

%N Heinz numbers of integer partitions of m >= 0 whose length times maximum is a multiple of m.

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

%C The enumeration of these partitions by sum is given by A326849.

%e The sequence of terms together with their prime indices begins:

%e 1: {}

%e 2: {1}

%e 3: {2}

%e 4: {1,1}

%e 5: {3}

%e 7: {4}

%e 8: {1,1,1}

%e 9: {2,2}

%e 11: {5}

%e 13: {6}

%e 16: {1,1,1,1}

%e 17: {7}

%e 19: {8}

%e 23: {9}

%e 25: {3,3}

%e 27: {2,2,2}

%e 28: {1,1,4}

%e 29: {10}

%e 31: {11}

%e 32: {1,1,1,1,1}

%e 37: {12}

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

%t Select[Range[100],#==1||Divisible[Max[primeMS[#]]*Length[primeMS[#]],Total[primeMS[#]]]&]

%Y Cf. A001222, A047993, A056239, A061395, A067538, A112798, A316413, A326836, A326843, A326847, A326849, A326851.

%K nonn

%O 1,2

%A _Gus Wiseman_, Jul 26 2019

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Last modified August 27 10:11 EDT 2024. Contains 375468 sequences. (Running on oeis4.)