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A302248
Irregular triangle read by rows in which the odd-indexed terms of the n-th row together with the even-indexed terms of the same row but listed in reverse order give the n-th row of triangle A299778.
0
1, 3, 2, 2, 7, 0, 3, 3, 12, 0, 0, 4, 4, 0, 15, 0, 0, 5, 5, 3, 9, 0, 0, 9, 6, 6, 0, 0, 28, 0, 0, 0, 7, 7, 0, 0, 12, 0, 0, 12, 8, 8, 8, 0, 0, 31, 0, 0, 0, 0, 9, 9, 0, 0, 0, 39, 0, 0, 0, 0, 10, 10, 0, 0, 0, 42, 0, 0, 0, 0, 11, 11, 5, 0, 0, 5, 18, 0, 0, 18, 0, 0, 12, 12, 0, 0, 0, 0, 60, 0, 0, 0, 0, 0, 13, 13, 0, 0, 5, 0
OFFSET
1,2
EXAMPLE
Triangle begins (rows 1..28):
1;
3;
2, 2;
7, 0;
3, 3;
12, 0, 0;
4, 4, 0;
15, 0, 0;
5, 5, 3;
9, 0, 0, 9;
6, 6, 0, 0;
28, 0, 0, 0;
7, 7, 0, 0;
12, 0, 0, 12;
8, 8, 8, 0, 0;
31, 0, 0, 0, 0;
9, 9, 0, 0, 0;
39, 0, 0, 0, 0;
10, 10, 0, 0, 0;
42, 0, 0, 0, 0;
11, 11, 5, 0, 0, 5;
18, 0, 0, 18, 0, 0;
12, 12, 0, 0, 0, 0;
60, 0, 0, 0, 0, 0;
13, 13, 0, 0, 5, 0;
21, 0, 0, 21, 0, 0;
14, 14, 6, 0, 0, 6;
56, 0, 0, 0, 0, 0, 0;
...
For n = 21 the 21st row of A299778 is [11, 5, 0, 5, 0, 11], so the 21st row of this triangle is [11, 11, 5, 0, 0, 5].
CROSSREFS
Row sums give A000203.
Row n has length A003056(n).
Column k starts in row A000217(k).
The number of nonzero terms in row n is A237271(n).
Column 1 is A241838.
The triangle with n rows contain A237590(n) nonzero terms.
Cf. A280850 (analog for subparts).
Sequence in context: A280850 A296508 A299778 * A235773 A089327 A280851
KEYWORD
nonn,tabf
AUTHOR
Omar E. Pol, Apr 10 2018
STATUS
approved