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A246688
Triangle in which n-th row lists lexicographically ordered increasing lists of parts of all partitions of n into distinct parts.
20
1, 2, 1, 2, 3, 1, 3, 4, 1, 4, 2, 3, 5, 1, 2, 3, 1, 5, 2, 4, 6, 1, 2, 4, 1, 6, 2, 5, 3, 4, 7, 1, 2, 5, 1, 3, 4, 1, 7, 2, 6, 3, 5, 8, 1, 2, 6, 1, 3, 5, 1, 8, 2, 3, 4, 2, 7, 3, 6, 4, 5, 9, 1, 2, 3, 4, 1, 2, 7, 1, 3, 6, 1, 4, 5, 1, 9, 2, 3, 5, 2, 8, 3, 7, 4, 6, 10
OFFSET
1,2
LINKS
EXAMPLE
Triangle begins:
[1];
[2];
[1,2], [3];
[1,3], [4];
[1,4], [2,3], [5];
[1,2,3], [1,5], [2,4], [6];
[1,2,4], [1,6], [2,5], [3,4], [7];
[1,2,5], [1,3,4], [1,7], [2,6], [3,5], [8];
[1,2,6], [1,3,5], [1,8], [2,3,4], [2,7], [3,6], [4,5], [9];
[1,2,3,4], [1,2,7], [1,3,6], [1,4,5], [1,9], [2,3,5], [2,8], [3,7], [4,6], [10];
MAPLE
b:= proc(n, i) b(n, i):= `if`(n=0, [[]], `if`(i>n, [],
[map(x->[i, x[]], b(n-i, i+1))[], b(n, i+1)[]]))
end:
T:= n-> map(x-> x[], b(n, 1))[]:
seq(T(n), n=1..12);
MATHEMATICA
T[n_] := Module[{ip, lg}, ip = Reverse /@ Select[ IntegerPartitions[n], # == DeleteDuplicates[#]&]; lg = Length /@ ip // Max; SortBy[PadRight[#, lg]&][ip]];
Table[T[n], {n, 1, 12}] // Flatten (* Jean-François Alcover, Oct 21 2022 *)
CROSSREFS
Row lengths are A015723.
Row sums give A066189.
Last elements of rows are A000027.
Sequence in context: A358136 A325537 A072851 * A103627 A344088 A292595
KEYWORD
nonn,tabf
AUTHOR
Alois P. Heinz, Sep 01 2014
STATUS
approved