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A373415
Maximum of the n-th maximal run of squarefree numbers.
8
3, 7, 11, 15, 17, 19, 23, 26, 31, 35, 39, 43, 47, 51, 53, 55, 59, 62, 67, 71, 74, 79, 83, 87, 89, 91, 95, 97, 103, 107, 111, 115, 119, 123, 127, 131, 134, 139, 143, 146, 149, 151, 155, 159, 161, 163, 167, 170, 174, 179, 183, 187, 191, 195, 197, 199, 203, 206
OFFSET
1,1
COMMENTS
The minimum is given by A072284.
A run of a sequence (in this case A005117) is an interval of positions at which consecutive terms differ by one.
Consists of all squarefree numbers k such that k + 1 is not squarefree.
FORMULA
a(n) = A070321(A072284(n+1) - 1).
EXAMPLE
Row-maxima of:
1 2 3
5 6 7
10 11
13 14 15
17
19
21 22 23
26
29 30 31
33 34 35
37 38 39
41 42 43
46 47
51
53
55
57 58 59
MATHEMATICA
Last/@Split[Select[Range[100], SquareFreeQ], #1+1==#2&]//Most
CROSSREFS
Functional neighbors: A006093, A007674, A067774, A072284, A120992, A373413.
A005117 lists the squarefree numbers, first differences A076259.
A013929 lists the nonsquarefree numbers, first differences A078147.
Sequence in context: A196079 A285497 A079710 * A145832 A292637 A279608
KEYWORD
nonn
AUTHOR
Gus Wiseman, Jun 05 2024
STATUS
approved