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A329135
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Numbers whose differences of prime indices are an aperiodic word.
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8
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1, 2, 3, 4, 5, 6, 7, 9, 10, 11, 12, 13, 14, 15, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 28, 29, 31, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 65, 66, 67, 68, 69, 70, 71, 72, 73
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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. The multiset of prime indices of n is row n of A112798.
A sequence is aperiodic if its cyclic rotations are all different.
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LINKS
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EXAMPLE
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The sequence of terms together with their differences of prime indices begins:
1: ()
2: ()
3: ()
4: (0)
5: ()
6: (1)
7: ()
9: (0)
10: (2)
11: ()
12: (0,1)
13: ()
14: (3)
15: (1)
17: ()
18: (1,0)
19: ()
20: (0,2)
21: (2)
22: (4)
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MATHEMATICA
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primeMS[n_]:=If[n==1, {}, Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]];
aperQ[q_]:=Array[RotateRight[q, #1]&, Length[q], 1, UnsameQ];
Select[Range[100], aperQ[Differences[primeMS[#]]]&]
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CROSSREFS
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These are the Heinz numbers of the partitions counted by A329137.
Aperiodic compositions are A000740.
Aperiodic binary words are A027375.
Numbers whose binary expansion is aperiodic are A328594.
Numbers whose prime signature is aperiodic are A329139.
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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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