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A055884 Euler transform of partition triangle A008284. 18
1, 1, 2, 1, 2, 3, 1, 4, 4, 5, 1, 4, 8, 7, 7, 1, 6, 12, 16, 12, 11, 1, 6, 17, 25, 28, 19, 15, 1, 8, 22, 43, 49, 48, 30, 22, 1, 8, 30, 58, 87, 88, 77, 45, 30, 1, 10, 36, 87, 134, 167, 151, 122, 67, 42, 1, 10, 45, 113, 207, 270, 296, 247, 185, 97, 56, 1, 12, 54, 155, 295, 448, 510, 507, 394, 278, 139, 77 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
1,3
COMMENTS
Number of multiset partitions of length-k integer partitions of n. - Gus Wiseman, Nov 09 2018
LINKS
N. J. A. Sloane, Transforms
EXAMPLE
From Gus Wiseman, Nov 09 2018: (Start)
Triangle begins:
1
1 2
1 2 3
1 4 4 5
1 4 8 7 7
1 6 12 16 12 11
1 6 17 25 28 19 15
1 8 22 43 49 48 30 22
1 8 30 58 87 88 77 45 30
...
The fifth row {1, 4, 8, 7, 7} counts the following multiset partitions:
{{5}} {{1,4}} {{1,1,3}} {{1,1,1,2}} {{1,1,1,1,1}}
{{2,3}} {{1,2,2}} {{1},{1,1,2}} {{1},{1,1,1,1}}
{{1},{4}} {{1},{1,3}} {{1,1},{1,2}} {{1,1},{1,1,1}}
{{2},{3}} {{1},{2,2}} {{2},{1,1,1}} {{1},{1},{1,1,1}}
{{2},{1,2}} {{1},{1},{1,2}} {{1},{1,1},{1,1}}
{{3},{1,1}} {{1},{2},{1,1}} {{1},{1},{1},{1,1}}
{{1},{1},{3}} {{1},{1},{1},{2}} {{1},{1},{1},{1},{1}}
{{1},{2},{2}}
(End)
MAPLE
h:= proc(n, i) option remember; expand(`if`(n=0, 1,
`if`(i<1, 0, h(n, i-1)+x*h(n-i, min(n-i, i)))))
end:
g:= proc(n, i, j) option remember; expand(`if`(j=0, 1, `if`(i<0, 0, add(
g(n, i-1, j-k)*x^(i*k)*binomial(coeff(h(n$2), x, i)+k-1, k), k=0..j))))
end:
b:= proc(n, i) option remember; expand(`if`(n=0, 1,
`if`(i<1, 0, add(b(n-i*j, i-1)*g(i$2, j), j=0..n/i))))
end:
T:= (n, k)-> coeff(b(n$2), x, k):
seq(seq(T(n, k), k=1..n), n=1..12); # Alois P. Heinz, Feb 17 2023
MATHEMATICA
sps[{}]:={{}}; sps[set:{i_, ___}]:=Join@@Function[s, Prepend[#, s]&/@sps[Complement[set, s]]]/@Cases[Subsets[set], {i, ___}];
mps[set_]:=Union[Sort[Sort/@(#/.x_Integer:>set[[x]])]&/@sps[Range[Length[set]]]];
Table[Length[Join@@mps/@IntegerPartitions[n, {k}]], {n, 5}, {k, n}] (* Gus Wiseman, Nov 09 2018 *)
CROSSREFS
Row sums give A001970.
Main diagonal gives A000041.
Columns k=1-2 give: A057427, A052928.
T(n+2,n+1) gives A000070.
T(2n,n) gives A360468.
Sequence in context: A162507 A091298 A306641 * A055889 A125930 A210790
KEYWORD
nonn,tabl
AUTHOR
Christian G. Bower, Jun 09 2000
STATUS
approved

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Last modified April 19 03:30 EDT 2024. Contains 371782 sequences. (Running on oeis4.)