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A320324
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Numbers of which each prime index has the same number of prime factors, counted with multiplicity.
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29
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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, 47, 49, 51, 53, 55, 59, 61, 64, 67, 71, 73, 75, 79, 81, 83, 85, 89, 91, 93, 97, 99, 101, 103, 107, 109, 113, 121, 123, 125, 127, 128, 131, 135, 137, 139, 149, 151, 153
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OFFSET
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1,2
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COMMENTS
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A prime index of n is a number m such that prime(m) divides n.
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LINKS
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EXAMPLE
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The terms together with their corresponding multiset multisystems (A302242):
1: {}
2: {{}}
3: {{1}}
4: {{},{}}
5: {{2}}
7: {{1,1}}
8: {{},{},{}}
9: {{1},{1}}
11: {{3}}
13: {{1,2}}
15: {{1},{2}}
16: {{},{},{},{}}
17: {{4}}
19: {{1,1,1}}
23: {{2,2}}
25: {{2},{2}}
27: {{1},{1},{1}}
29: {{1,3}}
31: {{5}}
32: {{},{},{},{},{}}
33: {{1},{3}}
37: {{1,1,2}}
41: {{6}}
43: {{1,4}}
45: {{1},{1},{2}}
47: {{2,3}}
49: {{1,1},{1,1}}
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MATHEMATICA
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Select[Range[100], SameQ@@PrimeOmega/@PrimePi/@First/@FactorInteger[#]&]
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PROG
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(PARI) is(n) = #Set(apply(p -> bigomega(primepi(p)), factor(n)[, 1]~))<=1 \\ Rémy Sigrist, Oct 11 2018
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CROSSREFS
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Cf. A001222, A038041, A112798, A302242, A306017, A317583, A319066, A319169, A320325, A322794, A326533, A326534, A326535, A326536, A326537.
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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