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A235794
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Triangle read by rows: T(n,k), n>=1, k>=1, in which column k starts with k zeros and then lists the odd numbers interleaved with k zeros, and the first element of column k is in row k(k+1)/2.
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10
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0, 1, 0, 0, 3, 0, 0, 1, 5, 0, 0, 0, 0, 0, 7, 3, 0, 0, 0, 1, 9, 0, 0, 0, 0, 5, 0, 0, 11, 0, 0, 0, 0, 0, 3, 0, 13, 7, 0, 1, 0, 0, 0, 0, 0, 15, 0, 0, 0, 0, 0, 9, 5, 0, 0, 17, 0, 0, 0, 0, 0, 0, 0, 3, 0, 19, 11, 0, 0, 1, 0, 0, 7, 0, 0, 0, 21, 0, 0, 0, 0, 0, 0
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OFFSET
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1,5
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COMMENTS
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It appears that the alternating row sums give A120444, the first differences of A004125, i.e., sum_{k=1..A003056(n))} (-1)^(k-1)*T(n,k) = A120444(n).
Row n has length A003056(n) hence the first element of column k is in row A000217(k).
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LINKS
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EXAMPLE
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Triangle begins:
0;
1;
0, 0;
3, 0;
0, 1;
5, 0, 0;
0, 0, 0;
7, 3, 0;
0, 0, 1;
9, 0, 0, 0;
0, 5, 0, 0;
11, 0, 0, 0;
0, 0, 3, 0;
13, 7, 0, 1;
0, 0, 0, 0, 0;
15, 0, 0, 0, 0;
0, 9, 5, 0, 0;
17, 0, 0, 0, 0;
0, 0, 0, 3, 0;
19, 11, 0, 0, 1;
0, 0, 7, 0, 0, 0;
21, 0, 0, 0, 0, 0;
0, 13, 0, 0, 0, 0;
23, 0, 0, 5, 0, 0;
...
For n = 14 the 14th row of triangle is 13, 7, 0, 1, and the alternating sum is 13 - 7 + 0 - 1 = 5, the same as A120444(14) = 5.
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CROSSREFS
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Cf. A000203, A000217, A003056, A004125, A120444, A196020, A211343, A228813, A231345, A231347, A235791, A236104, A236106, A236112.
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KEYWORD
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nonn,tabf
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AUTHOR
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STATUS
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approved
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