A050342
Expansion of Product_{m>=1} (1+x^m)^A000009(m).
Original entry on oeis.org
1, 1, 1, 3, 4, 7, 12, 19, 30, 49, 77, 119, 186, 286, 438, 670, 1014, 1528, 2300, 3437, 5119, 7603, 11241, 16564, 24343, 35650, 52058, 75820, 110115, 159510, 230522, 332324, 477994, 686044, 982519, 1404243, 2003063, 2851720, 4052429, 5748440, 8140007, 11507125
Offset: 0
4=(4)=(3)+(1)=(3+1)=(2+1)+(1).
From _Gus Wiseman_, Oct 11 2018: (Start)
a(n) is the number of set systems (sets of sets) whose multiset union is an integer partition of n. For example, the a(1) = 1 through a(6) = 12 set systems are:
{{1}} {{2}} {{3}} {{4}} {{5}} {{6}}
{{1,2}} {{1,3}} {{1,4}} {{1,5}}
{{1},{2}} {{1},{3}} {{2,3}} {{2,4}}
{{1},{1,2}} {{1},{4}} {{1,2,3}}
{{2},{3}} {{1},{5}}
{{1},{1,3}} {{2},{4}}
{{2},{1,2}} {{1},{1,4}}
{{1},{2,3}}
{{2},{1,3}}
{{3},{1,2}}
{{1},{2},{3}}
{{1},{2},{1,2}}
(End)
-
g:= proc(n, i) option remember; `if`(n=0, 1,
`if`(i<1, 0, g(n, i-1)+`if`(i>n, 0, g(n-i, i-1))))
end:
b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0,
add(binomial(g(i, i), j)*b(n-i*j, i-1), j=0..n/i)))
end:
a:= n-> b(n, n):
seq(a(n), n=0..50); # Alois P. Heinz, May 19 2013
-
g[n_, i_] := g[n, i] = If[n==0, 1, If[i<1, 0, g[n, i-1] + If[i>n, 0, g[n-i, i-1]]]]; b[n_, i_] := b[n, i] = If[n==0, 1, If[i<1, 0, Sum[Binomial[g[i, i], j]*b[n-i*j, i-1], {j, 0, n/i}]]]; a[n_] := b[n, n]; Table[a[n], {n, 0, 50}] (* Jean-François Alcover, Dec 19 2015, after Alois P. Heinz *)
nn=10;Table[SeriesCoefficient[Product[(1+x^k)^PartitionsQ[k],{k,nn}],{x,0,n}],{n,0,nn}] (* Gus Wiseman, Oct 11 2018 *)
A358914
Number of twice-partitions of n into distinct strict partitions.
Original entry on oeis.org
1, 1, 1, 3, 4, 7, 13, 20, 32, 51, 83, 130, 206, 320, 496, 759, 1171, 1786, 2714, 4104, 6193, 9286, 13920, 20737, 30865, 45721, 67632, 99683, 146604, 214865, 314782, 459136, 668867, 972425, 1410458, 2040894, 2950839, 4253713, 6123836, 8801349, 12627079
Offset: 0
The a(1) = 1 through a(6) = 13 twice-partitions:
((1)) ((2)) ((3)) ((4)) ((5)) ((6))
((21)) ((31)) ((32)) ((42))
((2)(1)) ((3)(1)) ((41)) ((51))
((21)(1)) ((3)(2)) ((321))
((4)(1)) ((4)(2))
((21)(2)) ((5)(1))
((31)(1)) ((21)(3))
((31)(2))
((3)(21))
((32)(1))
((41)(1))
((3)(2)(1))
((21)(2)(1))
This is the distinct case of
A270995.
The case of strictly decreasing sums is
A279785.
The case of constant sums is
A279791.
For distinct instead of weakly decreasing sums we have
A336343.
This is the twice-partition case of
A358913.
A001970 counts multiset partitions of integer partitions.
A055887 counts sequences of partitions.
A330462 counts set systems by total sum and length.
A358830 counts twice-partitions with distinct lengths.
Cf.
A000009,
A000219,
A075900,
A271619,
A296122,
A304969,
A321449,
A336342,
A358901,
A358906,
A358907.
-
twiptn[n_]:=Join@@Table[Tuples[IntegerPartitions/@ptn],{ptn,IntegerPartitions[n]}];
Table[Length[Select[twiptn[n],UnsameQ@@#&&And@@UnsameQ@@@#&]],{n,0,10}]
-
seq(n,k)={my(u=Vec(eta(x^2 + O(x*x^n))/eta(x + O(x*x^n))-1)); Vec(prod(k=1, n, my(c=u[k]); sum(j=0, min(c,n\k), x^(j*k)*c!/(c-j)!, O(x*x^n))))} \\ Andrew Howroyd, Dec 31 2022
A330459
Number of set partitions of set-systems with total sum n.
Original entry on oeis.org
1, 1, 1, 4, 6, 11, 26, 42, 78, 148, 280, 481, 867, 1569, 2742, 4933, 8493, 14857, 25925, 44877, 77022, 132511, 226449, 385396, 657314, 1111115, 1875708, 3157379, 5309439, 8885889, 14861478, 24760339, 41162971, 68328959, 113099231, 186926116, 308230044
Offset: 0
The a(6) = 26 partitions:
((6)) ((15)) ((123)) ((1)(2)(12))
((24)) ((1)(14)) ((1))((2)(12))
((1)(5)) ((1)(23)) ((12))((1)(2))
((2)(4)) ((2)(13)) ((2))((1)(12))
((1))((5)) ((3)(12)) ((1))((2))((12))
((2))((4)) ((1))((14))
((1))((23))
((1)(2)(3))
((2))((13))
((3))((12))
((1))((2)(3))
((2))((1)(3))
((3))((1)(2))
((1))((2))((3))
Cf.
A007713,
A050342,
A050343,
A279375,
A279785,
A283877,
A294617,
A330460,
A330462,
A323787-
A323795,
A330452-
A330459.
-
ppl[n_,k_]:=Switch[k,0,{n},1,IntegerPartitions[n],_,Join@@Table[Union[Sort/@Tuples[ppl[#,k-1]&/@ptn]],{ptn,IntegerPartitions[n]}]];
Table[Length[Select[ppl[n,3],And[UnsameQ@@Join@@#,And@@UnsameQ@@@Join@@#]&]],{n,0,10}]
-
\\ here L is A000009 and BellP is A000110 as series.
L(n)={eta(x^2 + O(x*x^n))/eta(x + O(x*x^n))}
BellP(n)={serlaplace(exp( exp(x + O(x*x^n)) - 1))}
seq(n)={my(c=L(n), b=BellP(n), v=Vec(prod(k=1, n, (1 + x^k*y + O(x*x^n))^polcoef(c, k)))); vector(#v, n, my(r=v[n]); sum(k=0, n-1, polcoeff(b,k)*polcoef(r,k)))} \\ Andrew Howroyd, Dec 29 2019
A330460
Triangle read by rows where T(n,k) is the number of set partitions with k blocks and total sum n.
Original entry on oeis.org
1, 0, 1, 0, 1, 0, 0, 2, 1, 0, 0, 2, 1, 0, 0, 0, 3, 2, 0, 0, 0, 0, 4, 5, 1, 0, 0, 0, 0, 5, 6, 1, 0, 0, 0, 0, 0, 6, 9, 2, 0, 0, 0, 0, 0, 0, 8, 13, 3, 0, 0, 0, 0, 0, 0, 0, 10, 23, 10, 1, 0, 0, 0, 0, 0, 0, 0, 12, 27, 11, 1, 0, 0, 0, 0, 0, 0, 0, 0, 15, 40, 19, 2, 0, 0, 0, 0, 0, 0, 0, 0
Offset: 0
Triangle begins:
1
0 1
0 1 0
0 2 1 0
0 2 1 0 0
0 3 2 0 0 0
0 4 5 1 0 0 0
0 5 6 1 0 0 0 0
0 6 9 2 0 0 0 0 0
0 8 13 3 0 0 0 0 0 0
0 10 23 10 1 0 0 0 0 0 0
0 12 27 11 1 0 0 0 0 0 0 0
0 15 40 19 2 0 0 0 0 0 0 0 0
Row n = 8 counts the following set partitions:
{{8}} {{1},{7}} {{1},{2},{5}}
{{3,5}} {{2},{6}} {{1},{3},{4}}
{{2,6}} {{3},{5}}
{{1,7}} {{1},{3,4}}
{{1,3,4}} {{1},{2,5}}
{{1,2,5}} {{2},{1,5}}
{{3},{1,4}}
{{4},{1,3}}
{{5},{1,2}}
Cf.
A000110,
A008277,
A050342,
A060016,
A072706,
A270995,
A271619,
A279375,
A279785,
A326701,
A330459,
A330462,
A330463,
A330759.
-
b:= proc(n, i, k) option remember; `if`(i*(i+1)/2 k*
b(n-i, t, k)+b(n-i, t, k+1))(min(n-i, i-1))))
end:
T:= n-> (p-> seq(coeff(p, x, i), i=0..n))(b(n$2, 0)):
seq(T(n), n=0..15); # Alois P. Heinz, Dec 29 2019
-
ppl[n_,k_]:=Switch[k,0,{n},1,IntegerPartitions[n],_,Join@@Table[Union[Sort/@Tuples[ppl[#,k-1]&/@ptn]],{ptn,IntegerPartitions[n]}]];
Table[Length[Select[ppl[n,2],Length[#]==k&&And[UnsameQ@@#,UnsameQ@@Join@@#]&]],{n,0,10},{k,0,n}]
(* Second program: *)
b[n_, i_, k_] := b[n, i, k] = If[i(i+1)/2 < n, 0, If[n == 0, x^k, b[n, i-1, k] + Function[t, k*b[n-i, t, k] + b[n-i, t, k + 1]][Min[n-i, i-1]]]];
T[n_] := PadRight[CoefficientList[b[n, n, 0], x], n + 1];
T /@ Range[0, 15] // Flatten (* Jean-François Alcover, May 16 2021, after Alois P. Heinz *)
-
A(n)={my(v=Vec(prod(k=1, n, 1 + x^k*y + O(x*x^n)))); vector(#v, n, my(p=v[n]); vector(n, k, sum(i=k, n, polcoef(p,i-1)*stirling(i-1, k-1, 2))))}
{my(T=A(12)); for(n=1, #T, print(T[n]))} \\ Andrew Howroyd, Dec 29 2019
A330463
Triangle read by rows where T(n,k) is the number of k-element sets of nonempty multisets of positive integers with total sum n.
Original entry on oeis.org
1, 0, 1, 0, 2, 0, 0, 3, 2, 0, 0, 5, 4, 0, 0, 0, 7, 11, 1, 0, 0, 0, 11, 20, 6, 0, 0, 0, 0, 15, 40, 16, 0, 0, 0, 0, 0, 22, 68, 40, 3, 0, 0, 0, 0, 0, 30, 120, 91, 11, 0, 0, 0, 0, 0, 0, 42, 195, 186, 41, 0, 0, 0, 0, 0, 0, 0, 56, 320, 367, 105, 3, 0, 0, 0, 0, 0, 0
Offset: 0
Triangle begins:
1
0 1
0 2 0
0 3 2 0
0 5 4 0 0
0 7 11 1 0 0
0 11 20 6 0 0 0
0 15 40 16 0 0 0 0
0 22 68 40 3 0 0 0 0
...
Row n = 5 counts the following sets of multisets:
{{5}} {{1},{4}} {{1},{2},{1,1}}
{{1,4}} {{2},{3}}
{{2,3}} {{1},{1,3}}
{{1,1,3}} {{1},{2,2}}
{{1,2,2}} {{2},{1,2}}
{{1,1,1,2}} {{3},{1,1}}
{{1,1,1,1,1}} {{1},{1,1,2}}
{{1,1},{1,2}}
{{2},{1,1,1}}
{{1},{1,1,1,1}}
{{1,1},{1,1,1}}
-
b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0, add(binomial(
combinat[numbpart](i), j)*expand(b(n-i*j, i-1)*x^j), j=0..n/i)))
end:
T:= n-> (p-> seq(coeff(p, x, i), i=0..n))(b(n$2)):
seq(T(n), n=0..14); # Alois P. Heinz, Dec 30 2019
-
ppl[n_,k_]:=Switch[k,0,{n},1,IntegerPartitions[n],_,Join@@Table[Union[Sort/@Tuples[ppl[#,k-1]&/@ptn]],{ptn,IntegerPartitions[n]}]];
Table[Length[Select[ppl[n,2],And[UnsameQ@@#,Length[#]==k]&]],{n,0,10},{k,0,n}]
(* Second program: *)
b[n_, i_] := b[n, i] = If[n == 0, 1, If[i<1, 0, Sum[Binomial[
PartitionsP[i], j]*Expand[b[n - i*j, i - 1]*x^j], {j, 0, n/i}]]];
T[n_] := Function[p, Table[Coefficient[p, x, i], {i, 0, n}]][b[n, n]];
T /@ Range[0, 14] // Flatten (* Jean-François Alcover, May 18 2021, after Alois P. Heinz *)
-
A(n)={my(v=Vec(prod(k=1, n, (1 + x^k*y + O(x*x^n))^numbpart(k)))); vector(#v, n, Vecrev(v[n],n))}
{my(T=A(12)); for(n=1, #T, print(T[n]))} \\ Andrew Howroyd, Dec 29 2019
A330461
Array read by antidiagonals where A(n,k) is the number of multiset partitions with k levels that are strict at all levels and have total sum n.
Original entry on oeis.org
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 2, 3, 1, 1, 1, 1, 3, 4, 4, 1, 1, 1, 1, 4, 7, 7, 5, 1, 1, 1, 1, 5, 12, 14, 11, 6, 1, 1, 1, 1, 6, 19, 29, 25, 16, 7, 1, 1, 1, 1, 8, 30, 57, 60, 41, 22, 8, 1, 1, 1, 1, 10, 49, 110, 141, 111, 63, 29, 9, 1, 1, 1
Offset: 0
Array begins:
k=0 k=1 k=2 k=3 k=4 k=5 k=6
-----------------------------
n=0: 1 1 1 1 1 1 1
n=1: 1 1 1 1 1 1 1
n=2: 1 1 1 1 1 1 1
n=3: 1 2 3 4 5 6 7
n=4: 1 2 4 7 11 16 22
n=5: 1 3 7 14 25 41 63
n=6: 1 4 12 29 60 111 189
For example, the A(5,3) = 14 partitions are:
{{5}} {{1}}{{4}}
{{14}} {{2}}{{3}}
{{23}} {{1}}{{13}}
{{1}{4}} {{2}}{{12}}
{{2}{3}} {{1}}{{1}{3}}
{{1}{13}} {{2}}{{1}{2}}
{{2}{12}} {{1}}{{1}{12}}
Cf.
A001970,
A004111,
A007713,
A060016,
A273873,
A279375,
A279785,
A294617,
A306186,
A323718,
A323790,
A330462.
-
spl[n_,0]:={n};
spl[n_,k_]:=Select[Join@@Table[Union[Sort/@Tuples[spl[#,k-1]&/@ptn]],{ptn,IntegerPartitions[n]}],UnsameQ@@#&];
Table[Length[spl[n-k,k]],{n,0,10},{k,0,n}]
-
WeighT(v)={Vec(exp(x*Ser(dirmul(v, vector(#v,n,(-1)^(n-1)/n))))-1,-#v)}
M(n, k=n)={my(L=List(), v=vector(n,i,1)); listput(L, concat([1], v)); for(j=1, k, v=WeighT(v); listput(L, concat([1], v))); Mat(Col(L))~}
{ my(A=M(7)); for(i=1, #A, print(A[i,])) } \\ Andrew Howroyd, Dec 31 2019
A360764
Number T(n,k) of sets of nonempty strict integer partitions with a total of k parts and total sum of n; triangle T(n,k), n>=0, 0<=k<=max(i:T(n,i)>0), read by rows.
Original entry on oeis.org
1, 0, 1, 0, 1, 0, 1, 2, 0, 1, 2, 1, 0, 1, 4, 2, 0, 1, 4, 6, 1, 0, 1, 6, 8, 4, 0, 1, 6, 13, 9, 1, 0, 1, 8, 18, 16, 6, 0, 1, 8, 24, 29, 13, 2, 0, 1, 10, 30, 43, 29, 6, 0, 1, 10, 39, 64, 52, 19, 1, 0, 1, 12, 46, 89, 89, 42, 7, 0, 1, 12, 56, 122, 139, 85, 22, 1
Offset: 0
T(6,1) = 1: {[6]}.
T(6,2) = 4: {[1],[5]}, {[2],[4]}, {[1,5]}, {[2,4]}.
T(6,3) = 6: {[1,2,3]}, {[1],[1,4]}, {[1],[2,3]}, {[2],[1,3]}, {[3],[1,2]}, {[1],[2],[3]}.
T(6,4) = 1: {[1],[2],[1,2]}.
Triangle T(n,k) begins:
1;
0, 1;
0, 1;
0, 1, 2;
0, 1, 2, 1;
0, 1, 4, 2;
0, 1, 4, 6, 1;
0, 1, 6, 8, 4;
0, 1, 6, 13, 9, 1;
0, 1, 8, 18, 16, 6;
0, 1, 8, 24, 29, 13, 2;
0, 1, 10, 30, 43, 29, 6;
0, 1, 10, 39, 64, 52, 19, 1;
...
-
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-1)))))
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), 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-> (p-> seq(coeff(p, x, i), i=0..degree(p)))(b(n$2)):
seq(T(n), n=0..14);
-
h[n_, i_] := h[n, i] = Expand[If[n == 0, 1, If[i < 1, 0, h[n, i - 1] + x*h[n - i, Min[n - i, i - 1]]]]];
g[n_, i_, j_] := g[n, i, j] = Expand[If[j == 0, 1, If[i<0, 0, Sum[g[n, i - 1, j - k]*x^(i*k)*Binomial[Coefficient[h[n, n], x, i], k], {k, 0, j}]]]];
b[n_, i_] := b[n, i] = Expand[If[n == 0, 1, If[i < 1, 0, Sum[b[n - i*j, i - 1]*g[i, i, j], {j, 0, n/i}]]]] ;
T[n_] := CoefficientList[b[n, n], x];
Table[T[n], {n, 0, 14}] // Flatten (* Jean-François Alcover, Nov 17 2023, after Alois P. Heinz *)
A358913
Number of finite sequences of distinct sets with total sum n.
Original entry on oeis.org
1, 1, 1, 4, 6, 11, 28, 45, 86, 172, 344, 608, 1135, 2206, 4006, 7689, 13748, 25502, 47406, 86838, 157560, 286642, 522089, 941356, 1718622, 3079218, 5525805, 9902996, 17788396, 31742616, 56694704, 100720516, 178468026, 317019140, 560079704, 991061957
Offset: 0
The a(1) = 1 through a(5) = 11 sequences of sets:
({1}) ({2}) ({3}) ({4}) ({5})
({1,2}) ({1,3}) ({1,4})
({1},{2}) ({1},{3}) ({2,3})
({2},{1}) ({3},{1}) ({1},{4})
({1},{1,2}) ({2},{3})
({1,2},{1}) ({3},{2})
({4},{1})
({1},{1,3})
({1,2},{2})
({1,3},{1})
({2},{1,2})
The case of strictly decreasing sums is
A279785.
This is the distinct case of
A304969.
This is the case of
A358906 with strict partitions.
The version for compositions instead of strict partitions is
A358907.
The case of twice-partitions is
A358914.
A001970 counts multiset partitions of integer partitions.
A055887 counts sequences of partitions.
A330462 counts set systems by total sum and length.
A358830 counts twice-partitions with distinct lengths.
-
g:= proc(n) option remember; `if`(n=0, 1, add(g(n-j)*add(
`if`(d::odd, d, 0), d=numtheory[divisors](j)), j=1..n)/n)
end:
b:= proc(n, i, p) option remember; `if`(n=0, p!, `if`(i<1, 0,
add(binomial(g(i), j)*b(n-i*j, i-1, p+j), j=0..n/i)))
end:
a:= n-> b(n$2, 0):
seq(a(n), n=0..35); # Alois P. Heinz, Feb 13 2024
-
ptnseq[n_]:=Join@@Table[Tuples[IntegerPartitions/@comp],{comp,Join@@Permutations/@IntegerPartitions[n]}];
Table[Length[Select[ptnseq[n],UnsameQ@@#&&And@@UnsameQ@@@#&]],{n,0,10}]
Showing 1-8 of 8 results.
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