OFFSET
1
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|
...
CROSSREFS
KEYWORD
nonn,tabf
AUTHOR
Omar E. Pol, Dec 17 2016
STATUS
approved