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A279038
Triangle of multinomial coefficients read by rows (ordered by decreasing size of the greatest part).
3
1, 1, 1, 1, 2, 3, 1, 6, 8, 3, 6, 1, 24, 30, 20, 20, 15, 10, 1, 120, 144, 90, 90, 40, 120, 40, 15, 45, 15, 1, 720, 840, 504, 504, 420, 630, 210, 280, 210, 420, 70, 105, 105, 21, 1, 5040, 5760, 3360, 3360, 2688, 4032, 1344, 1260, 3360, 1260, 2520, 420, 1120, 1120, 1680, 1120, 112, 105, 420, 210, 28, 1
OFFSET
0,5
COMMENTS
The ordering of integer partitions used in this version is also called:
- canonical ordering
- graded reverse lexicographic ordering
- magma (software) ordering
by opposition to the ordering used by Abramowitz and Stegun.
LINKS
EXAMPLE
First rows are:
1
1
1 1
2 3 1
6 8 3 6 1
24 30 20 20 15 10 1
120 144 90 90 40 120 40 15 45 15 1
720 840 504 504 420 630 210 280 210 420 70 105 105 21 1
...
MAPLE
b:= proc(n, i) option remember; `if`(n=0, [1],
`if`(i<1, [], [seq(map(x-> x*i^j*j!,
b(n-i*j, i-1))[], j=[iquo(n, i)-t$t=0..n/i])]))
end:
T:= n-> map(x-> n!/x, b(n$2))[]:
seq(T(n), n=0..10); # Alois P. Heinz, Dec 04 2016
MATHEMATICA
Flatten[Table[
Map[n!/Times @@ ((First[#]^Length[#]*Factorial[Length[#]]) & /@
Split[#]) &, IntegerPartitions[n]], {n, 1, 8}]]
(* Second program: *)
b[n_, i_] := b[n, i] = If[n == 0, {1},
If[i < 1, {}, Flatten@Table[#*i^j*j!& /@
b[n - i*j, i - 1], {j, Quotient[n, i] - Range[0, n/i]}]]];
T[n_] := n!/#& /@ b[n, n];
T /@ Range[0, 10] // Flatten (* Jean-François Alcover, Jun 01 2021, after Alois P. Heinz *)
CROSSREFS
Cf. A000041 (number of partitions of n, length of each row).
Cf. A128628 (triangle of partition lengths)
Cf. A036039 (a different ordering), A102189 (row reversed version of A036039).
Row sums give A000142.
Sequence in context: A347945 A036039 A324254 * A092271 A054115 A100822
KEYWORD
nonn,tabf,look,easy
AUTHOR
EXTENSIONS
One term for row n=0 prepended by Alois P. Heinz, Dec 04 2016
STATUS
approved