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Triangle read by rows in which row n lists the elements of the n-th row of A237048 and then the elements of the same row but in reverse order.
9

%I #26 Dec 27 2016 23:22:38

%S 1,1,1,1,1,1,1,1,1,0,0,1,1,1,1,1,1,0,1,1,0,1,1,1,0,0,1,1,1,0,0,0,0,1,

%T 1,1,1,1,1,1,1,0,0,1,1,0,0,1,1,1,0,0,0,0,1,1,1,0,1,0,0,1,0,1,1,1,0,0,

%U 0,0,1,1,1,0,0,1,1,0,0,1,1,1,1,0,1,1,0,1,1,1,1,0,0,0,0,0,0,0,0,1,1,1,0,0,0,0,0,0,1,1

%N Triangle read by rows in which row n lists the elements of the n-th row of A237048 and then the elements of the same row but in reverse order.

%e Triangle begins (rows 1..20):

%e 1, 1;

%e 1, 1;

%e 1, 1, 1, 1;

%e 1, 0, 0, 1;

%e 1, 1, 1, 1;

%e 1, 0, 1, 1, 0, 1;

%e 1, 1, 0, 0, 1, 1;

%e 1, 0, 0, 0, 0, 1;

%e 1, 1, 1, 1, 1, 1;

%e 1, 0, 0, 1, 1, 0, 0, 1;

%e 1, 1, 0, 0, 0, 0, 1, 1;

%e 1, 0, 1, 0, 0, 1, 0, 1;

%e 1, 1, 0, 0, 0, 0, 1, 1;

%e 1, 0, 0, 1, 1, 0, 0, 1;

%e 1, 1, 1, 0, 1, 1, 0, 1, 1, 1;

%e 1, 0, 0, 0, 0, 0, 0, 0, 0, 1;

%e 1, 1, 0, 0, 0, 0, 0, 0, 1, 1;

%e 1, 0, 1, 1, 0, 0, 1, 1, 0, 1;

%e 1, 1, 0, 0, 0, 0, 0, 0, 1, 1;

%e 1, 0, 0, 0, 1, 1, 0, 0, 0, 1;

%e ...

%e Illustration of initial terms as an isosceles triangle:

%e Row _ _

%e 1 _|1|1|_

%e 2 _|1 _|_ 1|_

%e 3 _|1 |1|1| 1|_

%e 4 _|1 _|0|0|_ 1|_

%e 5 _|1 |1 _|_ 1| 1|_

%e 6 _|1 _|0|1|1|0|_ 1|_

%e 7 _|1 |1 |0|0| 1| 1|_

%e 8 _|1 _|0 _|0|0|_ 0|_ 1|_

%e 9 _|1 |1 |1 _|_ 1| 1| 1|_

%e 10 _|1 _|0 |0|1|1|0| 0|_ 1|_

%e 11 _|1 |1 _|0|0|0|0|_ 1| 1|_

%e 12 _|1 _|0 |1 |0|0| 1| 0|_ 1|_

%e 13 _|1 |1 |0 _|0|0|_ 0| 1| 1|_

%e 14 _|1 _|0 _|0|1 _|_ 1|0|_ 0|_ 1|_

%e 15 _|1 |1 |1 |0|1|1|0| 1| 1| 1|_

%e 16 |1 |0 |0 |0|0|0|0| 0| 0| 1|

%e ...

%e The above triangle is related to the triangle A237593 and to the left part of the front view of the pyramid described A245092. For more information about the pyramid and the symmetric representation of sigma see A237593.

%Y Row n has length A279891(n).

%Y Row sums give A054844.

%Y One half of the row sums give A001227.

%Y Cf. A196020, A235791, A236104, A237048, A237270, A237271, A237591, A237593, A239657, A245092, A249351, A261699, A262611, A262626, A275601, A279387, A279733.

%K nonn,tabf

%O 1

%A _Omar E. Pol_, Dec 17 2016