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A375300
Triangle T(n,k) read by rows that has the A001710(n)-th lexicographic permutation of [1,...,n] as row n.
0
1, 1, 2, 2, 1, 3, 2, 4, 3, 1, 3, 2, 5, 4, 1, 3, 6, 5, 4, 2, 1, 4, 3, 7, 6, 5, 2, 1, 4, 8, 7, 6, 5, 3, 2, 1, 5, 4, 9, 8, 7, 6, 3, 2, 1, 5, 10, 9, 8, 7, 6, 4, 3, 2, 1, 6, 5, 11, 10, 9, 8, 7, 4, 3, 2, 1, 6, 12, 11, 10, 9, 8, 7, 5, 4, 3, 2, 1, 7, 6, 13, 12, 11, 10, 9, 8, 5, 4, 3, 2, 1
OFFSET
1,3
EXAMPLE
The triangle begins
1,
1, 2,
2, 1, 3,
2, 4, 3, 1,
3, 2, 5, 4, 1,
3, 6, 5, 4, 2, 1,
4, 3, 7, 6, 5, 2, 1,
4, 8, 7, 6, 5, 3, 2, 1,
5, 4, 9, 8, 7, 6, 3, 2, 1,
5, 10, 9, 8, 7, 6, 4, 3, 2, 1,
...
PROG
(PARI) a375300_row(n) = if (n<2, [1], my(m=n!\2); forperm(n, p, m--; if (m==0, return(Vec(p)))))
CROSSREFS
KEYWORD
nonn,tabl,easy
AUTHOR
Hugo Pfoertner, Aug 24 2024
STATUS
approved