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A328027
Irregular triangle read by rows where row n lists, in weakly increasing order, the differences between consecutive divisors of n.
3
1, 2, 1, 2, 4, 1, 1, 3, 6, 1, 2, 4, 2, 6, 1, 3, 5, 10, 1, 1, 1, 2, 6, 12, 1, 5, 7, 2, 2, 10, 1, 2, 4, 8, 16, 1, 1, 3, 3, 9, 18, 1, 1, 2, 5, 10, 2, 4, 14, 1, 9, 11, 22, 1, 1, 1, 2, 2, 4, 12, 4, 20, 1, 11, 13, 2, 6, 18, 1, 2, 3, 7, 14, 28, 1, 1, 1, 2, 4, 5, 15
OFFSET
1,2
EXAMPLE
Triangle begins:
{}
1
2
1 2
4
1 1 3
6
1 2 4
2 6
1 3 5
10
1 1 1 2 6
12
1 5 7
2 2 10
1 2 4 8
16
1 1 3 3 9
18
1 1 2 5 10
2 4 14
1 9 11
22
1 1 1 2 2 4 12
For example, the divisors of 18 are {1,2,3,6,9,18}, with differences {1,1,3,3,9}, which is row 18.
MATHEMATICA
Table[Sort[Differences[Divisors[n]]], {n, 30}]
CROSSREFS
Same as A193829 with rows sorted in increasing order.
Same as A328025 with rows reversed.
Row sums are A001477.
Row lengths are A000005.
First column is A060680.
Sequence in context: A097865 A105245 A105246 * A193829 A337714 A198069
KEYWORD
nonn,tabf
AUTHOR
Gus Wiseman, Oct 02 2019
STATUS
approved