A279693 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.

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, 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, 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

Offset

1

Links

Table of n, a(n) for n=1..110.

Example

Triangle begins (rows 1..20):
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;
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, 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;
1, 0, 1, 1, 0, 0, 1, 1, 0, 1;
1, 1, 0, 0, 0, 0, 0, 0, 1, 1;
1, 0, 0, 0, 1, 1, 0, 0, 0, 1;
...
Illustration of initial terms as an isosceles triangle:
Row                                 _ _
1                                 _|1|1|_
2                               _|1 _|_ 1|_
3                             _|1  |1|1|  1|_
4                           _|1   _|0|0|_   1|_
5                         _|1    |1 _|_ 1|    1|_
6                       _|1     _|0|1|1|0|_     1|_
7                     _|1      |1  |0|0|  1|      1|_
8                   _|1       _|0 _|0|0|_ 0|_       1|_
9                 _|1        |1  |1 _|_ 1|  1|        1|_
10              _|1         _|0  |0|1|1|0|  0|_         1|_
11            _|1          |1   _|0|0|0|0|_   1|          1|_
12          _|1           _|0  |1  |0|0|  1|  0|_           1|_
13        _|1            |1    |0 _|0|0|_ 0|    1|            1|_
14      _|1             _|0   _|0|1 _|_ 1|0|_   0|_             1|_
15    _|1              |1    |1  |0|1|1|0|  1|    1|              1|_
16   |1                |0    |0  |0|0|0|0|  0|    0|                1|
...
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.

Crossrefs

Row n has length A279891(n).

Row sums give A054844.

One half of the row sums give A001227.

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

Sequence in context: A110242 A356315 A273592 * A368992 A334465 A054527

Adjacent sequences: A279690 A279691 A279692 * A279694 A279695 A279696

Keyword

nonn,tabf

Author

Omar E. Pol, Dec 17 2016

Status

approved