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Total weight of the n-th twice-odd-factored multiset partition.
32

%I #8 Apr 08 2018 20:11:09

%S 0,1,1,2,2,1,2,2,1,3,3,2,2,3,2,1,2,3,3,3,1,2,3,2,4,2,4,2,4,1,3,4,3,1,

%T 3,3,2,3,3,2,4,1,2,3,4,4,2,4,2,3,2,3,4,3,1,4,3,3,4,3,2,2,3,1,3,5,5,4,

%U 2,2,3,3,3,5,2,4,3,2,1,5,4,2,3,2,4,5,4,4

%N Total weight of the n-th twice-odd-factored multiset partition.

%C A multiset partition is a finite multiset of finite nonempty multisets of positive integers. The n-th twice-odd-factored multiset partition is constructed by factoring 2n + 1 into prime numbers and then factoring each prime index into prime numbers and taking their prime indices.

%F a(n) = A302242(2n + 1).

%e Sequence of multiset partitions begins: (), ((1)), ((2)), ((11)), ((1)(1)), ((3)), ((12)), ((1)(2)), ((4)), ((111)), ((1)(11)), ((22)), ((2)(2)), ((1)(1)(1)), ((13)), ((5)), ((1)(3)), ((2)(11)), ((112)), ((1)(12)), ((6)).

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

%t Table[Sum[PrimeOmega[k],{k,primeMS[2n-1]}],{n,100}]

%Y Cf. A003963, A007716, A034691, A048673, A056239, A061775, A063834 A064216, A096443, A249620, A255397, A255906, A275024, A279789, A281113, A299757, A302242.

%K nonn

%O 0,4

%A _Gus Wiseman_, Apr 03 2018