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A334946
Irregular triangle read by rows: T(n,k) is the number of partitions of n into k consecutive parts that differ by 6, and the first element of column k is in the row that is the k-th octagonal number (A000567).
5
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 0, 0, 1, 1, 1, 1, 0, 0, 1, 1, 0, 1, 0, 1, 1, 1, 0, 1, 1, 0, 0, 0, 1, 1, 1, 0, 1, 0, 0
OFFSET
1
COMMENTS
T(n,k) is 0 or 1, so T(n,k) represents the "existence" of the mentioned partition: 1 = exists, 0 = does not exist.
Since the trivial partition n is counted, so T(n,1) = 1.
This is also an irregular triangle read by rows: T(n,k), n >= 1, k >= 1, in which column k lists 1's interleaved with k-1 zeros, and the first element of column k is in the row that is the k-th octagonal number.
This triangle can be represented with a diagram of overlapping curves, in which every column of triangle is represented by a periodic curve.
For a general theorem about the triangles of this family see A303300.
EXAMPLE
Triangle begins (rows 1..24).
1;
1;
1;
1;
1;
1;
1;
1, 1;
1, 0;
1, 1;
1, 0;
1, 1;
1, 0;
1, 1;
1, 0;
1, 1;
1, 0;
1, 1;
1, 0;
1, 1;
1, 0, 1;
1, 1, 0;
1, 0, 0;
1, 1, 1;
...
For n = 24 there are three partitions of 24 into consecutive parts that differ by 6, including 24 as a valid partition. They are [24], [15, 9] and [14, 8, 2], so the 24th row of this triangle is [1, 1, 1].
CROSSREFS
Row sums give A334948.
Triangles of the same family where the parts differ by m are: A051731 (m=0), A237048 (m=1), A303300 (m=2), A330887 (m=3), A334460 (m=4), A334465 (m=5), this sequence (m=6).
Sequence in context: A086299 A131364 A152066 * A225595 A228813 A122255
KEYWORD
nonn,tabf
AUTHOR
Omar E. Pol, May 27 2020
STATUS
approved