A261697 Irregular triangle read by rows in which row n lists the odd divisors of n in the ordering given by A261699.

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, 3, 9, 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, 3, 15, 5, 1, 31, 1, 1, 33, 3, 11, 1, 17, 1, 35, 5, 7, 1, 3, 9, 1, 37, 1, 19, 1, 39, 3, 13, 1, 5, 1, 41, 1, 3, 21, 7, 1, 43, 1, 11, 1, 45, 3, 5, 15, 9

Offset

1,4

Comments

Positive terms of A261699.

Note that this ordering is unusual.

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 A261698 from which differs at a(34), or T(18,2).

Links

Table of n, a(n) for n=1..108.

Example

List of divisors of 45 from distinct sequences:
45th row of triangle A182469: 1, 3, 5, 9, 15, 45.
45th row of triangle A261698: 1, 45, 3, 15, 5, 9.
45th row of this triangle...: 1, 45, 3, 5, 15, 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,  3,  9;
  1, 19;
  1,  5;
  1, 21,  3,  7;
  ...

Crossrefs

Cf. A000593, A001227, A027750, A182469, A261698, A261699.

Sequence in context: A255670 A182469 A329984 * A261698 A124738 A131086

Adjacent sequences: A261694 A261695 A261696 * A261698 A261699 A261700

Keyword

nonn,tabf

Author

Omar E. Pol, Sep 21 2015

Status

approved