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A328674
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Numbers whose distinct prime indices have no consecutive divisible parts.
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3
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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, 35, 37, 41, 43, 45, 47, 49, 51, 53, 55, 59, 61, 64, 67, 69, 71, 73, 75, 77, 79, 81, 83, 85, 89, 91, 93, 95, 97, 99, 101, 103, 105, 107, 109, 113, 119, 121, 123, 125, 127, 128, 131, 135
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OFFSET
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1,2
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COMMENTS
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First differs from A316476 in having 105, with prime indices {2, 3, 4}.
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.
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LINKS
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EXAMPLE
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The sequence of terms together with their prime indices begins:
1: {}
2: {1}
3: {2}
4: {1,1}
5: {3}
7: {4}
8: {1,1,1}
9: {2,2}
11: {5}
13: {6}
15: {2,3}
16: {1,1,1,1}
17: {7}
19: {8}
23: {9}
25: {3,3}
27: {2,2,2}
29: {10}
31: {11}
32: {1,1,1,1,1}
For example, 45 is in the sequence because its distinct prime indices are {2,3} and 2 is not a divisor of 3.
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MATHEMATICA
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Select[Range[100], !MatchQ[PrimePi/@First/@FactorInteger[#], {___, x_, y_, ___}/; Divisible[y, x]]&]
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CROSSREFS
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These are the Heinz numbers of the partitions counted by A328675.
Partitions without consecutive divisibilities are A328171.
Compositions without consecutive divisibilities are A328460.
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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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