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
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
A330655
Number of balanced reduced multisystems of weight n whose atoms cover an initial interval of positive integers.
Original entry on oeis.org
1, 1, 2, 12, 138, 2652, 78106, 3256404, 182463296, 13219108288, 1202200963522, 134070195402644, 17989233145940910, 2858771262108762492, 530972857546678902490, 113965195745030648131036, 27991663753030583516229824, 7800669355870672032684666900, 2448021231611414334414904013956
Offset: 0
The a(0) = 1 through a(3) = 12 multisystems:
{} {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
A330475.
The case where the atoms are all different is
A005121.
The case where the atoms are all equal is
A318813.
Multiset partitions of normal multisets are
A255906.
Series-reduced rooted trees with normal leaves are
A316651.
-
allnorm[n_]:=If[n<=0,{{}},Function[s,Array[Count[s,y_/;y<=#]+1&,n]]/@Subsets[Range[n-1]+1]];
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]]]];
totm[m_]:=Prepend[Join@@Table[totm[p],{p,Select[mps[m],1
-
EulerT(v)={Vec(exp(x*Ser(dirmul(v, vector(#v, n, 1/n))))-1, -#v)}
R(n,k)={my(v=vector(n), u=vector(n)); v[1]=k; for(n=1, #v, u += v*sum(j=n, #v, (-1)^(j-n)*binomial(j-1,n-1)); v=EulerT(v)); u}
seq(n)={concat([1], sum(k=1, n, R(n, k)*sum(r=k, n, binomial(r, k)*(-1)^(r-k))))} \\ Andrew Howroyd, Dec 30 2019
A330663
Number of non-isomorphic balanced reduced multisystems of weight n and maximum depth.
Original entry on oeis.org
1, 1, 2, 4, 20, 140, 1411
Offset: 0
Non-isomorphic representatives of the a(2) = 2 through a(4) = 20 multisystems:
{1,1} {{1},{1,1}} {{{1}},{{1},{1,1}}}
{1,2} {{1},{1,2}} {{{1,1}},{{1},{1}}}
{{1},{2,3}} {{{1}},{{1},{1,2}}}
{{2},{1,1}} {{{1,1}},{{1},{2}}}
{{{1}},{{1},{2,2}}}
{{{1,1}},{{2},{2}}}
{{{1}},{{1},{2,3}}}
{{{1,1}},{{2},{3}}}
{{{1}},{{2},{1,1}}}
{{{1,2}},{{1},{1}}}
{{{1}},{{2},{1,2}}}
{{{1,2}},{{1},{2}}}
{{{1}},{{2},{1,3}}}
{{{1,2}},{{1},{3}}}
{{{1}},{{2},{3,4}}}
{{{1,2}},{{3},{4}}}
{{{2}},{{1},{1,1}}}
{{{2}},{{1},{1,3}}}
{{{2}},{{3},{1,1}}}
{{{2,3}},{{1},{1}}}
The non-maximal version is
A330474.
The case where the leaves are sets (as opposed to multisets) is
A330677.
The case with all atoms distinct is
A000111.
The case with all atoms equal is (also)
A000111.
Cf.
A000311,
A004114,
A005121,
A006472,
A007716,
A048816,
A141268,
A306186,
A330470,
A330655,
A330664.
A330665
Number of balanced reduced multisystems of maximal depth whose atoms are the prime indices of n.
Original entry on oeis.org
1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 2, 1, 2, 1, 1, 1, 5, 1, 1, 1, 2, 1, 3, 1, 5, 1, 1, 1, 7, 1, 1, 1, 5, 1, 3, 1, 2, 2, 1, 1, 16, 1, 2, 1, 2, 1, 5, 1, 5, 1, 1, 1, 11, 1, 1, 2, 16, 1, 3, 1, 2, 1, 3, 1, 27, 1, 1, 2, 2, 1, 3, 1, 16, 2, 1, 1, 11, 1
Offset: 1
The a(n) multisystems for n = 2, 6, 12, 24, 48:
{1} {1,2} {{1},{1,2}} {{{1}},{{1},{1,2}}} {{{{1}}},{{{1}},{{1},{1,2}}}}
{{2},{1,1}} {{{1,1}},{{1},{2}}} {{{{1}}},{{{1,1}},{{1},{2}}}}
{{{1}},{{2},{1,1}}} {{{{1},{1}}},{{{1}},{{1,2}}}}
{{{1,2}},{{1},{1}}} {{{{1},{1,1}}},{{{1}},{{2}}}}
{{{2}},{{1},{1,1}}} {{{{1,1}}},{{{1}},{{1},{2}}}}
{{{{1}}},{{{1}},{{2},{1,1}}}}
{{{{1}}},{{{1,2}},{{1},{1}}}}
{{{{1},{1}}},{{{2}},{{1,1}}}}
{{{{1},{1,2}}},{{{1}},{{1}}}}
{{{{1,1}}},{{{2}},{{1},{1}}}}
{{{{1}}},{{{2}},{{1},{1,1}}}}
{{{{1},{2}}},{{{1}},{{1,1}}}}
{{{{1,2}}},{{{1}},{{1},{1}}}}
{{{{2}}},{{{1}},{{1},{1,1}}}}
{{{{2}}},{{{1,1}},{{1},{1}}}}
{{{{2},{1,1}}},{{{1}},{{1}}}}
The last nonzero term in row n of
A330667 is a(n).
The non-maximal version is
A318812.
Other labeled versions are
A330675 (strongly normal) and
A330676 (normal).
Cf.
A001055,
A005121,
A005804,
A050336,
A213427,
A292505,
A317144,
A318849,
A320160,
A330474,
A330475,
A330679.
-
primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
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]]]];
totm[m_]:=Prepend[Join@@Table[totm[p],{p,Select[mps[m],1
A330676
Number of balanced reduced multisystems of weight n and maximum depth whose atoms cover an initial interval of positive integers.
Original entry on oeis.org
1, 1, 2, 8, 70, 1012, 21944, 665708, 26917492, 1399033348, 90878863352, 7214384973908, 687197223963640, 77354805301801012, 10158257981179981304, 1539156284259756811748, 266517060496258245459352, 52301515332984084095078308, 11546416513975694879642736152
Offset: 0
The a(0) = 1 through a(3) = 8 multisystems:
{} {1} {1,1} {{1},{1,1}}
{1,2} {{1},{1,2}}
{{1},{2,2}}
{{1},{2,3}}
{{2},{1,1}}
{{2},{1,2}}
{{2},{1,3}}
{{3},{1,2}}
The case with all atoms equal is
A000111.
The case with all atoms different is
A006472.
The version allowing all depths is
A330655.
The version where the atoms are the prime indices of n is
A330665.
The strongly normal version is
A330675.
The version where the degrees are the prime indices of n is
A330728.
Multiset partitions of normal multisets are
A255906.
Series-reduced rooted trees with normal leaves are
A316651.
Cf.
A000669,
A001055,
A005121,
A005804,
A318812,
A330469,
A330474,
A330654,
A330664,
A330677,
A330679.
-
allnorm[n_]:=If[n<=0,{{}},Function[s,Array[Count[s,y_/;y<=#]+1&,n]]/@Subsets[Range[n-1]+1]];
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]]]];
totm[m_]:=Prepend[Join@@Table[totm[p],{p,Select[mps[m],1
-
EulerT(v)={Vec(exp(x*Ser(dirmul(v, vector(#v, n, 1/n))))-1, -#v)}
R(n, k)={my(v=vector(n), u=vector(n)); v[1]=k; for(n=1, #v, for(i=n, #v, u[i] += v[i]*(-1)^(i-n)*binomial(i-1, n-1)); v=EulerT(v)); u}
seq(n)={concat([1], sum(k=1, n, R(n, k)*sum(r=k, n, binomial(r, k)*(-1)^(r-k))))} \\ Andrew Howroyd, Dec 30 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}]
A330664
Number of non-isomorphic balanced reduced multisystems of maximum depth whose degrees (atom multiplicities) are the weakly decreasing prime indices of n.
Original entry on oeis.org
1, 1, 1, 1, 1, 2, 2, 1, 4, 5, 5, 7, 16, 16, 27, 2, 61, 33, 272, 27, 123, 61, 1385, 27, 78, 272, 95, 123, 7936, 362
Offset: 1
Non-isomorphic representatives of the a(n) multisystems for n = 2, 3, 6, 9, 10, 12 (commas and outer brackets elided):
1 11 {1}{12} {{1}}{{1}{22}} {{1}}{{1}{12}} {{1}}{{1}{23}}
{2}{11} {{11}}{{2}{2}} {{11}}{{1}{2}} {{11}}{{2}{3}}
{{1}}{{2}{12}} {{1}}{{2}{11}} {{1}}{{2}{13}}
{{12}}{{1}{2}} {{12}}{{1}{1}} {{12}}{{1}{3}}
{{2}}{{1}{11}} {{2}}{{1}{13}}
{{2}}{{3}{11}}
{{23}}{{1}{1}}
The non-maximal version is
A330666.
The case of constant or strict atoms is
A000111.
Non-isomorphic multiset partitions whose degrees are the prime indices of n are
A318285.
Cf.
A004114,
A005121,
A007716,
A048816,
A141268,
A306186,
A318846,
A318848,
A330470,
A330474,
A330663.
A330728
Number of balanced reduced multisystems of maximum depth whose degrees (atom multiplicities) are the prime indices of n.
Original entry on oeis.org
1, 1, 1, 1, 1, 2, 2, 3, 7, 5, 5, 11, 16, 16, 27, 18, 61, 62, 272, 45, 123, 61, 1385, 105, 152, 272, 501, 211, 7936, 362
Offset: 1
The a(n) multisystems for n = 3, 6, 8, 9, 10, 12 (commas and outer brackets elided):
11 {1}{12} {1}{23} {{1}}{{1}{22}} {{1}}{{1}{12}} {{1}}{{1}{23}}
{2}{11} {2}{13} {{11}}{{2}{2}} {{11}}{{1}{2}} {{11}}{{2}{3}}
{3}{12} {{1}}{{2}{12}} {{1}}{{2}{11}} {{1}}{{2}{13}}
{{12}}{{1}{2}} {{12}}{{1}{1}} {{12}}{{1}{3}}
{{2}}{{1}{12}} {{2}}{{1}{11}} {{1}}{{3}{12}}
{{2}}{{2}{11}} {{13}}{{1}{2}}
{{22}}{{1}{1}} {{2}}{{1}{13}}
{{2}}{{3}{11}}
{{23}}{{1}{1}}
{{3}}{{1}{12}}
{{3}}{{2}{11}}
The version with distinct atoms is
A006472.
The non-maximal version is
A318846.
Final terms in each row of
A330727.
-
nrmptn[n_]:=Join@@MapIndexed[Table[#2[[1]],{#1}]&,If[n==1,{},Flatten[Cases[Reverse[FactorInteger[n]],{p_,k_}:>Table[PrimePi[p],{k}]]]]];
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]]]];
totm[m_]:=Prepend[Join@@Table[totm[p],{p,Select[mps[m],1
A330726
Number of balanced reduced multisystems of maximum depth whose atoms are positive integers summing to n.
Original entry on oeis.org
1, 1, 2, 3, 7, 17, 54, 199, 869, 4341, 24514, 154187
Offset: 0
The a(1) = 1 through a(5) = 17 multisystems (commas elided):
{1} {2} {3} {4} {5}
{11} {12} {22} {23}
{{1}{11}} {13} {14}
{{1}{12}} {{1}{13}}
{{2}{11}} {{1}{22}}
{{{1}}{{1}{11}}} {{2}{12}}
{{{11}}{{1}{1}}} {{3}{11}}
{{{1}}{{1}{12}}}
{{{11}}{{1}{2}}}
{{{1}}{{2}{11}}}
{{{12}}{{1}{1}}}
{{{2}}{{1}{11}}}
{{{{1}}}{{{1}}{{1}{11}}}}
{{{{1}}}{{{11}}{{1}{1}}}}
{{{{1}{1}}}{{{1}}{{11}}}}
{{{{1}{11}}}{{{1}}{{1}}}}
{{{{11}}}{{{1}}{{1}{1}}}}
The case with all atoms equal to 1 is
A000111.
The non-maximal version is
A330679.
Cf.
A000669,
A002846,
A005121,
A141268,
A196545,
A213427,
A317145,
A318813,
A330663,
A330665,
A330675,
A330676,
A330728.
-
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]]]];
totm[m_]:=Prepend[Join@@Table[totm[p],{p,Select[mps[m],1
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