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%I #5 Oct 01 2019 09:48:42
%S 1,15,33,51,55,85,91,93,123,155,161,165,177,187,201,203,205,249,255,
%T 295,299,301,327,329,335,341,377,381,415,451,465,471,511,527,537,545,
%U 553,559,561,573,611,615,633,635,649,667,679,697,703,707,723,737,785,831
%N Nonprime squarefree numbers whose prime indices all have the same Omega (number of prime factors counted with multiplicity).
%C A prime index of n is a number m such that prime(m) divides n. The multiset of prime indices of n is row n of A112798.
%H Gus Wiseman, <a href="/A038041/a038041.txt">Sequences counting and ranking multiset partitions whose part lengths, sums, or averages are constant or strict.</a>
%e The sequence of terms together with their prime indices begins:
%e 1: {}
%e 15: {2,3}
%e 33: {2,5}
%e 51: {2,7}
%e 55: {3,5}
%e 85: {3,7}
%e 91: {4,6}
%e 93: {2,11}
%e 123: {2,13}
%e 155: {3,11}
%e 161: {4,9}
%e 165: {2,3,5}
%e 177: {2,17}
%e 187: {5,7}
%e 201: {2,19}
%e 203: {4,10}
%e 205: {3,13}
%e 249: {2,23}
%e 255: {2,3,7}
%e 295: {3,17}
%t Select[Range[1000],!PrimeQ[#]&&SquareFreeQ[#]&&SameQ@@PrimeOmega/@PrimePi/@First/@FactorInteger[#]&]
%Y The case including primes and nonsquarefree numbers is A320324.
%Y The version for sum of prime indices is A327901.
%Y The version for mean of prime indices is A327902.
%Y Cf. A001222, A038041, A056239, A078175, A112798, A306017, A306021, A316413, A317583, A322794, A327908.
%K nonn
%O 1,2
%A _Gus Wiseman_, Sep 30 2019
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