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A261698
Irregular triangle read by rows in which row n lists the odd divisors of n in the order as follows: the smallest, the largest, the second smallest, the second largest, the third smallest, the third largest, and so on.
3
1, 1, 1, 3, 1, 1, 5, 1, 3, 1, 7, 1, 1, 9, 3, 1, 5, 1, 11, 1, 3, 1, 13, 1, 7, 1, 15, 3, 5, 1, 1, 17, 1, 9, 3, 1, 19, 1, 5, 1, 21, 3, 7, 1, 11, 1, 23, 1, 3, 1, 25, 5, 1, 13, 1, 27, 3, 9, 1, 7, 1, 29, 1, 15, 3, 5, 1, 31, 1, 1, 33, 3, 11, 1, 17, 1, 35, 5, 7, 1, 9, 3, 1, 37, 1, 19, 1, 39, 3, 13, 1, 5, 1, 41, 1, 21, 3, 7, 1, 43, 1, 11, 1, 45, 3, 15, 5, 9
OFFSET
1,4
COMMENTS
Also the odd numbers of A210959.
Row lengths give A001227.
Row sums give A000593.
Another version of A182469 from which differs at a(14), or T(9,2).
For a similar version see A261697 from which differs at a(34), or T(18,2).
EXAMPLE
List of divisors of 45 from distinct sequences:
45th row of triangle A182469: 1, 3, 5, 9, 15, 45.
45th row of triangle A261697: 1, 45, 3, 5, 15, 9.
45th row of this triangle...: 1, 45, 3, 15, 5, 9.
Triangle begins:
1;
1;
1, 3;
1;
1, 5;
1, 3;
1, 7;
1;
1, 9, 3;
1, 5;
1, 11;
1, 3;
1, 13;
1, 7;
1, 15, 3, 5;
1;
1, 17;
1, 9, 3;
1, 19;
1, 5;
1, 21, 3, 7;
...
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
Omar E. Pol, Sep 21 2015
STATUS
approved