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%I #21 Feb 07 2021 06:26:01
%S 1,2,3,4,5,7,8,9,11,13,15,16,17,19,23,25,27,29,31,32,33,37,41,43,45,
%T 47,49,51,53,55,59,61,64,67,71,73,75,79,81,83,85,89,91,93,97,99,101,
%U 103,107,109,113,121,123,125,127,128,131,135,137,139,149,151,153
%N Numbers of which each prime index has the same number of prime factors, counted with multiplicity.
%C A prime index of n is a number m such that prime(m) divides n.
%H Amiram Eldar, <a href="/A320324/b320324.txt">Table of n, a(n) for n = 1..10000</a>
%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 terms together with their corresponding multiset multisystems (A302242):
%e 1: {}
%e 2: {{}}
%e 3: {{1}}
%e 4: {{},{}}
%e 5: {{2}}
%e 7: {{1,1}}
%e 8: {{},{},{}}
%e 9: {{1},{1}}
%e 11: {{3}}
%e 13: {{1,2}}
%e 15: {{1},{2}}
%e 16: {{},{},{},{}}
%e 17: {{4}}
%e 19: {{1,1,1}}
%e 23: {{2,2}}
%e 25: {{2},{2}}
%e 27: {{1},{1},{1}}
%e 29: {{1,3}}
%e 31: {{5}}
%e 32: {{},{},{},{},{}}
%e 33: {{1},{3}}
%e 37: {{1,1,2}}
%e 41: {{6}}
%e 43: {{1,4}}
%e 45: {{1},{1},{2}}
%e 47: {{2,3}}
%e 49: {{1,1},{1,1}}
%t Select[Range[100],SameQ@@PrimeOmega/@PrimePi/@First/@FactorInteger[#]&]
%o (PARI) is(n) = #Set(apply(p -> bigomega(primepi(p)), factor(n)[,1]~))<=1 \\ _Rémy Sigrist_, Oct 11 2018
%Y Cf. A001222, A038041, A112798, A302242, A306017, A317583, A319066, A319169, A320325, A322794, A326533, A326534, A326535, A326536, A326537.
%K nonn
%O 1,2
%A _Gus Wiseman_, Oct 10 2018
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