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A366421
a(n) is the floor of the n-th improper fraction (including the ones of the type n/n) sorted by increasing numerator+denominator, then by numerator.
0
1, 2, 1, 3, 1, 4, 1, 2, 5, 1, 2, 6, 1, 1, 3, 7, 1, 2, 3, 8, 1, 1, 2, 4, 9, 1, 1, 2, 4, 10, 1, 1, 2, 3, 5, 11, 1, 1, 2, 3, 5, 12, 1, 1, 1, 2, 3, 6, 13, 1, 1, 2, 2, 4, 6, 14, 1, 1, 1, 2, 3, 4, 7, 15, 1, 1, 1, 2, 3, 4, 7, 16, 1, 1, 1, 2, 2, 3, 5, 8, 17, 1, 1, 1, 2, 2, 3, 5, 8, 18
OFFSET
1,2
FORMULA
a(n) = floor[A138099(n)/(A216607(n)+1)]
EXAMPLE
The first such fraction is 1/1, followed by 2/1, 2/2, 3/1, 3/2 and so on, then a(1)=[1/1]=1, a(2)=[2/1]=2, a(3)=[2/2]=1, a(4)=[3/1]=3, a(5)=[3/2]=1 and so on, where [.] is the floor function.
Terms begin:
[1/1]=1,
[2/1]=2,
[2/2]=1, [3/1]=3,
[3/2]=1, [4/1]=4,
[3/3]=1, [4/2]=2, [5/1]=5,
[4/3]=1, [5/2]=2, [6/1]=6,
...
CROSSREFS
Sequence in context: A210256 A332422 A229944 * A218533 A328578 A351613
KEYWORD
nonn
AUTHOR
Mariano Masiello, Nov 16 2023
STATUS
approved