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Irregular triangle read by rows in which row n lists the odd divisors of n in the ordering given by A261699.
4

%I #32 Jul 29 2017 12:07:33

%S 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,

%T 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,

%U 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

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

%C Positive terms of A261699.

%C Note that this ordering is unusual.

%C Row lengths give A001227.

%C Row sums give A000593.

%C Another version of A182469 from which differs at a(14), or T(9,2).

%C For a similar version see A261698 from which differs at a(34), or T(18,2).

%e List of divisors of 45 from distinct sequences:

%e 45th row of triangle A182469: 1, 3, 5, 9, 15, 45.

%e 45th row of triangle A261698: 1, 45, 3, 15, 5, 9.

%e 45th row of this triangle...: 1, 45, 3, 5, 15, 9.

%e Triangle begins:

%e 1;

%e 1;

%e 1, 3;

%e 1;

%e 1, 5;

%e 1, 3;

%e 1, 7;

%e 1;

%e 1, 9, 3;

%e 1, 5;

%e 1, 11;

%e 1, 3;

%e 1, 13;

%e 1, 7;

%e 1, 15, 3, 5;

%e 1;

%e 1, 17;

%e 1, 3, 9;

%e 1, 19;

%e 1, 5;

%e 1, 21, 3, 7;

%e ...

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

%K nonn,tabf

%O 1,4

%A _Omar E. Pol_, Sep 21 2015