A035310
Let f(n) = number of ways to factor n = A001055(n); a(n) = sum of f(k) over all terms k in A025487 that have n factors.
Original entry on oeis.org
1, 4, 12, 47, 170, 750, 3255, 16010, 81199, 448156, 2579626, 15913058, 102488024, 698976419, 4976098729, 37195337408, 289517846210, 2352125666883, 19841666995265, 173888579505200, 1577888354510786, 14820132616197925, 143746389756336173, 1438846957477988926
Offset: 1
a(3) = 12 because there are 3 terms in A025487 with 3 factors, namely 8, 12, 30; and f(8)=3, f(12)=4, f(30)=5 and 3+4+5 = 12.
From _Gus Wiseman_, Dec 31 2019: (Start)
The a(1) = 1 through a(3) = 12 multiset partitions of strongly normal multisets:
{{1}} {{1,1}} {{1,1,1}}
{{1,2}} {{1,1,2}}
{{1},{1}} {{1,2,3}}
{{1},{2}} {{1},{1,1}}
{{1},{1,2}}
{{1},{2,3}}
{{2},{1,1}}
{{2},{1,3}}
{{3},{1,2}}
{{1},{1},{1}}
{{1},{1},{2}}
{{1},{2},{3}}
(End)
Sequence
A035341 counts the ordered cases. Tables
A093936 and
A095705 distribute the values; e.g. 81199 = 30 + 536 + 3036 + 6181 + 10726 + 11913 + 14548 + 13082 + 21147.
The case with empty intersection is
A317755.
The case of strict parts is
A330783.
Multiset partitions of integer partitions are
A001970.
Unlabeled multiset partitions are
A007716.
-
with(numtheory):
g:= proc(n, k) option remember;
`if`(n>k, 0, 1) +`if`(isprime(n), 0,
add(`if`(d>k, 0, g(n/d, d)), d=divisors(n) minus {1, n}))
end:
b:= proc(n, i, l)
`if`(n=0, g(mul(ithprime(t)^l[t], t=1..nops(l))$2),
`if`(i<1, 0, add(b(n-i*j, i-1, [l[], i$j]), j=0..n/i)))
end:
a:= n-> b(n$2, []):
seq(a(n), n=1..10); # Alois P. Heinz, May 26 2013
-
g[n_, k_] := g[n, k] = If[n > k, 0, 1] + If[PrimeQ[n], 0, Sum[If[d > k, 0, g[n/d, d]], {d, Divisors[n] ~Complement~ {1, n}}]]; b[n_, i_, l_] := If[n == 0, g[p = Product[Prime[t]^l[[t]], {t, 1, Length[l]}], p], If[i < 1, 0, Sum[b[n - i*j, i-1, Join[l, Array[i&, j]]], {j, 0, n/i}]]]; a[n_] := b[n, n, {}]; Table[Print[an = a[n]]; an, {n, 1, 13}] (* Jean-François Alcover, Dec 12 2013, after Alois P. Heinz *)
-
EulerT(v)={Vec(exp(x*Ser(dirmul(v, vector(#v, n, 1/n))))-1, -#v)}
D(p, n)={my(v=vector(n)); for(i=1, #p, v[p[i]]++); my(u=EulerT(v)); Vec(1/prod(k=1, n, 1 - u[k]*x^k + O(x*x^n))-1, -n)/prod(i=1, #v, i^v[i]*v[i]!)}
seq(n)={my(s=0); forpart(p=n, s+=D(p,n)); s} \\ Andrew Howroyd, Dec 30 2020
-
from sympy.core.cache import cacheit
from sympy import divisors, isprime, prime
from operator import mul
@cacheit
def g(n, k):
return (0 if n > k else 1) + (0 if isprime(n) else sum(g(n//d, d) for d in divisors(n)[1:-1] if d <= k))
@cacheit
def b(n, i, l):
if n==0:
p = reduce(mul, (prime(t + 1)**l[t] for t in range(len(l))))
return g(p, p)
else:
return 0 if i<1 else sum([b(n - i*j, i - 1, l + [i]*j) for j in range(n//i + 1)])
def a(n):
return b(n, n, [])
for n in range(1, 11): print(a(n)) # Indranil Ghosh, Aug 19 2017, after Maple code
A330465
Number of non-isomorphic series-reduced rooted trees whose leaves are multisets with a total of n elements.
Original entry on oeis.org
1, 4, 14, 87, 608, 5573, 57876, 687938, 9058892, 130851823, 2048654450, 34488422057, 620046639452, 11839393796270, 238984150459124, 5079583100918338, 113299159314626360, 2644085918303683758, 64393240540265515110, 1632731130253043991252, 43013015553755764179000
Offset: 1
Non-isomorphic representatives of the a(3) = 14 trees:
((1)((1)(1))) ((1)((1)(2))) ((1)((2)(3))) ((2)((1)(1)))
((1)(1)(1)) ((1)(1)(2)) ((1)(2)(3)) ((2)(1,1))
((1)(1,1)) ((1)(1,2)) ((1)(2,3))
(1,1,1) (1,1,2) (1,2,3)
The version where leaves are atoms is
A318231.
The case with sets as leaves is
A330624.
The case with disjoint sets as leaves is
A141268.
The singleton-reduced version is
A330470.
Cf.
A000311,
A000669,
A004114,
A005804,
A007716,
A281118,
A289501,
A292504,
A316651,
A316652,
A318812,
A319312,
A330471,
A330474,
A330625,
A339645.
-
\\ See links in A339645 for combinatorial species functions.
cycleIndexSeries(n)={my(v=vector(n), p=sEulerT(x*sv(1) + O(x*x^n))); v[1]=sv(1); for(n=2, #v, v[n] = polcoef( sEulerT(x*Ser(v[1..n])), n ) + polcoef(p,n)); x*Ser(v)}
InequivalentColoringsSeq(cycleIndexSeries(15)) \\ Andrew Howroyd, Dec 13 2020
A330475
Number of balanced reduced multisystems whose atoms constitute a strongly normal multiset of size n.
Original entry on oeis.org
1, 1, 2, 9, 85, 1143, 25270
Offset: 0
The a(0) = 1 through a(3) = 9 multisystems:
{} {1} {1,1} {1,1,1}
{1,2} {1,1,2}
{1,2,3}
{{1},{1,1}}
{{1},{1,2}}
{{1},{2,3}}
{{2},{1,1}}
{{2},{1,3}}
{{3},{1,2}}
The (weakly) normal version is
A330655.
The case where the atoms are {1..n} is
A005121.
The case where the atoms are all 1's is
A318813.
Multiset partitions of strongly normal multisets are
A035310.
-
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]]]];
strnorm[n_]:=Flatten[MapIndexed[Table[#2,{#1}]&,#]]&/@IntegerPartitions[n];
totm[m_]:=Prepend[Join@@Table[totm[p],{p,Select[mps[m],1
A330470
Number of non-isomorphic series/singleton-reduced rooted trees on a multiset of size n.
Original entry on oeis.org
1, 1, 2, 7, 39, 236, 1836, 16123, 162008, 1802945, 22012335, 291290460, 4144907830, 62986968311, 1016584428612, 17344929138791, 311618472138440, 5875109147135658, 115894178676866576, 2385755803919949337, 51133201045333895149, 1138659323863266945177, 26296042933904490636133
Offset: 0
Non-isomorphic representatives of the a(4) = 39 trees, with singleton leaves (x) replaced by just x:
(1111) (1112) (1122) (1123) (1234)
(1(111)) (1(112)) (1(122)) (1(123)) (1(234))
(11(11)) (11(12)) (11(22)) (11(23)) (12(34))
((11)(11)) (12(11)) (12(12)) (12(13)) ((12)(34))
(1(1(11))) (2(111)) ((11)(22)) (2(113)) (1(2(34)))
((11)(12)) (1(1(22))) (23(11))
(1(1(12))) ((12)(12)) ((11)(23))
(1(2(11))) (1(2(12))) (1(1(23)))
(2(1(11))) ((12)(13))
(1(2(13)))
(2(1(13)))
(2(3(11)))
The case with all atoms equal or all atoms different is
A000669.
Not requiring singleton-reduction gives
A330465.
Labeled versions are
A316651 (normal orderless) and
A330471 (strongly normal).
The case where the leaves are sets is
A330626.
Cf.
A000311,
A005121,
A005804,
A141268,
A213427,
A292504,
A292505,
A318812,
A318848,
A318849,
A330467,
A330469,
A330474,
A330624.
-
\\ See links in A339645 for combinatorial species functions.
cycleIndexSeries(n)={my(v=vector(n)); v[1]=sv(1); for(n=2, #v, v[n] = polcoef( sEulerT(x*Ser(v[1..n])), n )); x*Ser(v)}
InequivalentColoringsSeq(cycleIndexSeries(15)) \\ Andrew Howroyd, Dec 11 2020
A330467
Number of series-reduced rooted trees whose leaves are multisets whose multiset union is a strongly normal multiset of size n.
Original entry on oeis.org
1, 1, 4, 18, 154, 1614, 23733, 396190, 8066984, 183930948, 4811382339, 138718632336, 4451963556127, 155416836338920, 5920554613563841, 242873491536944706, 10725017764009207613, 505671090907469848248, 25415190929321149684700, 1354279188424092012064226
Offset: 0
The a(3) = 18 trees:
{1,1,1} {1,1,2} {1,2,3}
{{1},{1,1}} {{1},{1,2}} {{1},{2,3}}
{{1},{1},{1}} {{2},{1,1}} {{2},{1,3}}
{{1},{{1},{1}}} {{1},{1},{2}} {{3},{1,2}}
{{1},{{1},{2}}} {{1},{2},{3}}
{{2},{{1},{1}}} {{1},{{2},{3}}}
{{2},{{1},{3}}}
{{3},{{1},{2}}}
The singleton-reduced version is
A316652.
Not requiring weakly decreasing multiplicities gives
A330469.
The case where the leaves are sets is
A330625.
Cf.
A000311,
A000669,
A004114,
A005121,
A005804,
A141268,
A292504,
A292505,
A318812,
A318849,
A319312,
A330471,
A330475.
-
strnorm[n_]:=Flatten[MapIndexed[Table[#2,{#1}]&,#]]&/@IntegerPartitions[n];
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]]]];
multing[t_,n_]:=Array[(t+#-1)/#&,n,1,Times];
amemo[m_]:=amemo[m]=1+Sum[Product[multing[amemo[s[[1]]],Length[s]],{s,Split[c]}],{c,Select[mps[m],Length[#]>1&]}];
Table[Sum[amemo[m],{m,strnorm[n]}],{n,0,5}]
-
\\ See links in A339645 for combinatorial species functions.
cycleIndexSeries(n)={my(v=vector(n), p=sExp(x*sv(1) + O(x*x^n))); v[1]=sv(1); for(n=2, #v, v[n] = polcoef( sExp(x*Ser(v[1..n])), n ) + polcoef(p, n)); 1 + x*Ser(v)}
StronglyNormalLabelingsSeq(cycleIndexSeries(15)) \\ Andrew Howroyd, Dec 28 2020
A330625
Number of series-reduced rooted trees whose leaves are sets (not necessarily disjoint) with multiset union a strongly normal multiset of size n.
Original entry on oeis.org
1, 1, 3, 14, 123, 1330, 19694
Offset: 0
The a(1) = 1 through a(3) = 14 trees:
{1} {1,2} {1,2,3}
{{1},{1}} {{1},{1,2}}
{{1},{2}} {{1},{2,3}}
{{2},{1,3}}
{{3},{1,2}}
{{1},{1},{1}}
{{1},{1},{2}}
{{1},{2},{3}}
{{1},{{1},{1}}}
{{1},{{1},{2}}}
{{1},{{2},{3}}}
{{2},{{1},{1}}}
{{2},{{1},{3}}}
{{3},{{1},{2}}}
The generalization where the leaves are multisets is
A330467.
The singleton-reduced case is
A330628.
The case with all atoms distinct is
A005804.
The case with all atoms equal is
A196545.
The case where all leaves are singletons is
A330471.
-
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]]]];
strnorm[n_]:=Flatten[MapIndexed[Table[#2,{#1}]&,#]]&/@IntegerPartitions[n];
srtrees[m_]:=Prepend[Join@@Table[Tuples[srtrees/@p],{p,Select[mps[m],Length[#1]>1&]}],m];
Table[Sum[Length[Select[srtrees[s],FreeQ[#,{_,x_Integer,x_Integer,_}]&]],{s,strnorm[n]}],{n,0,5}]
A330628
Number of series/singleton-reduced rooted trees on strongly normal multisets of size n whose leaves are sets (not necessarily disjoint).
Original entry on oeis.org
1, 1, 1, 5, 42, 423, 5458, 80926
Offset: 0
The a(4) = 42 trees:
{{1}{1}{12}} {{12}{12}} {{1}{123}} {1234}
{{1}{{1}{12}}} {{1}{2}{12}} {{12}{13}} {{1}{234}}
{{1}{{2}{12}}} {{1}{1}{23}} {{12}{34}}
{{2}{{1}{12}}} {{1}{2}{13}} {{13}{24}}
{{1}{3}{12}} {{14}{23}}
{{1}{{1}{23}}} {{2}{134}}
{{1}{{2}{13}}} {{3}{124}}
{{1}{{3}{12}}} {{4}{123}}
{{2}{{1}{13}}} {{1}{2}{34}}
{{3}{{1}{12}}} {{1}{3}{24}}
{{1}{4}{23}}
{{2}{3}{14}}
{{2}{4}{13}}
{{3}{4}{12}}
{{1}{{2}{34}}}
{{1}{{3}{24}}}
{{1}{{4}{23}}}
{{2}{{1}{34}}}
{{2}{{3}{14}}}
{{2}{{4}{13}}}
{{3}{{1}{24}}}
{{3}{{2}{14}}}
{{3}{{4}{12}}}
{{4}{{1}{23}}}
{{4}{{2}{13}}}
{{4}{{3}{12}}}
The generalization where leaves are multisets is
A330471.
The non-singleton-reduced version is
A330625.
The case with all atoms distinct is
A000311.
Strongly normal multiset partitions are
A035310.
Cf.
A000669,
A004111,
A004114,
A005804,
A196545,
A281118,
A330465,
A330467,
A330624,
A330654,
A330668.
-
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]]]];
strnorm[n_]:=Flatten[MapIndexed[Table[#2,{#1}]&,#]]&/@IntegerPartitions[n];
ssrtrees[m_]:=Prepend[Join@@Table[Tuples[ssrtrees/@p],{p,Select[mps[m],Length[m]>Length[#1]>1&]}],m];
Table[Sum[Length[Select[ssrtrees[s],FreeQ[#,{_,x_Integer,x_Integer,_}]&]],{s,strnorm[n]}],{n,0,5}]
A330654
Number of series/singleton-reduced rooted trees on normal multisets of size n.
Original entry on oeis.org
1, 1, 2, 12, 112, 1444, 24099, 492434, 11913985
Offset: 0
The a(0) = 1 through a(3) = 12 trees:
{} {1} {1,1} {1,1,1}
{1,2} {1,1,2}
{1,2,2}
{1,2,3}
{{1},{1,1}}
{{1},{1,2}}
{{1},{2,2}}
{{1},{2,3}}
{{2},{1,1}}
{{2},{1,2}}
{{2},{1,3}}
{{3},{1,2}}
The strongly normal case is
A330471.
The case with all atoms distinct is
A000311.
The case with all atoms equal is
A196545.
Normal multiset partitions are
A255906.
-
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]]]];
allnorm[n_]:=If[n<=0,{{}},Function[s,Array[Count[s,y_/;y<=#]+1&,n]]/@Subsets[Range[n-1]+1]];
ssrtrees[m_]:=Prepend[Join@@Table[Tuples[ssrtrees/@p],{p,Select[mps[m],Length[m]>Length[#1]>1&]}],m];
Table[Sum[Length[ssrtrees[s]],{s,allnorm[n]}],{n,0,5}]
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