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A351284
Irregular triangle read by rows: the n-th row gives the x-values of the solutions of the equation 2*(x - 1)*y - (x - 3)*x = 2*n for 0 < x <= y.
2
2, 2, 2, 2, 3, 2, 2, 3, 2, 2, 3, 4, 2, 2, 3, 2, 4, 2, 3, 2, 5, 2, 3, 4, 2, 2, 3, 2, 4, 5, 2, 3, 2, 6, 2, 3, 4, 2, 5, 2, 3, 2, 4, 2, 3, 6, 2, 5, 2, 3, 4, 7, 2, 2, 3, 2, 4, 5, 6, 2, 3, 2, 2, 3, 4, 7, 2, 5, 2, 3, 6, 8, 2, 4, 2, 3, 2, 5, 2, 3, 4, 7, 2, 6, 2, 3, 2, 4, 5, 8
OFFSET
3,1
COMMENTS
Equivalently, the n-th row gives the column indices corresponding to n in the triangle A351153.
EXAMPLE
Triangle begins:
2;
2;
2;
2, 3;
2;
2, 3;
2;
2, 3, 4;
...
MATHEMATICA
Table[r={}; For[d=1, d<Floor[(Sqrt[1+8n]-1)/2], d++, If[Divisible[2n+(d-2)(d+1), 2d], AppendTo[r, d+1]]]; r, {n, 3, 43}]//Flatten
CROSSREFS
Cf. A341829, A351153, A136107 (row length or solutions number), A351285 (y-values).
Sequence in context: A074592 A089993 A220431 * A268317 A234092 A047931
KEYWORD
nonn,tabf
AUTHOR
Stefano Spezia, Feb 06 2022
STATUS
approved