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A340791
Irregular triangle read by rows in which row n lists the positive divisors of n that are >= sqrt(n) in decreasing order.
2
1, 2, 3, 4, 2, 5, 6, 3, 7, 8, 4, 9, 3, 10, 5, 11, 12, 6, 4, 13, 14, 7, 15, 5, 16, 8, 4, 17, 18, 9, 6, 19, 20, 10, 5, 21, 7, 22, 11, 23, 24, 12, 8, 6, 25, 5, 26, 13, 27, 9, 28, 14, 7, 29, 30, 15, 10, 6, 31, 32, 16, 8, 33, 11, 34, 17, 35, 7, 36, 18, 12, 9, 6, 37, 38, 19
OFFSET
1,2
COMMENTS
Reversing rows gives A161908.
EXAMPLE
Triangle begins:
1
2
3
4 2
5
6 3
7
8 4
9 3
10 5
11
12 6 4
13
14 7
15 5
16 8 4
17
18 9 6
19
20 10 5
21 7
22 11
23
24 12 8 6
PROG
(PARI) row(n) = Vecrev(select(x->(x>=sqrt(n)), divisors(n))); \\ Michel Marcus, Jan 22 2021
CROSSREFS
Cf. A038548 (row widths), A160180 (second column), A161908 (rows reversed), A340792.
Sequence in context: A286547 A157000 A026346 * A369422 A361020 A368693
KEYWORD
nonn,tabf
AUTHOR
Charles Kusniec, Jan 21 2021
STATUS
approved