A383014
Numbers whose prime indices can be partitioned into constant blocks with a common sum.
Original entry on oeis.org
1, 2, 3, 4, 5, 7, 8, 9, 11, 12, 13, 16, 17, 19, 23, 25, 27, 29, 31, 32, 36, 37, 40, 41, 43, 47, 48, 49, 53, 59, 61, 63, 64, 67, 71, 73, 79, 81, 83, 89, 97, 101, 103, 107, 108, 109, 112, 113, 121, 125, 127, 128, 131, 137, 139, 144, 149, 151, 157, 163, 167, 169
Offset: 1
The prime indices of 36 are {1,1,2,2}, and a partition into constant blocks with a common sum is: {{2},{2},{1,1}}, so 36 is in the sequence.
The prime indices of 43200 are {1,1,1,1,1,1,2,2,2,3,3}, and a partition into constant blocks with a common sum is: {{{1,1,1,1,1,1},{2,2,2},{3,3}}}, so 43200 is in the sequence.
The prime indices of 520000 are {1,1,1,1,1,1,3,3,3,3,6} and a partition into constant blocks with a common sum is: {{1,1,1,1,1,1},{3,3},{3,3},{6}}, so 520000 is in the sequence.
The terms together with their prime indices begin:
1: {}
2: {1}
3: {2}
4: {1,1}
5: {3}
7: {4}
8: {1,1,1}
9: {2,2}
11: {5}
12: {1,1,2}
13: {6}
16: {1,1,1,1}
17: {7}
19: {8}
23: {9}
25: {3,3}
27: {2,2,2}
29: {10}
31: {11}
32: {1,1,1,1,1}
36: {1,1,2,2}
37: {12}
40: {1,1,1,3}
Twice-partitions of this type (constant blocks with a common sum) are counted by
A279789.
For distinct sums we have the complement of
A381636.
For strict blocks we have the complement of
A381719.
For distinct sums and strict blocks we have the complement of
A381806.
These are the positions of positive terms in
A381995.
Partitions of this type are counted by
A383093.
A001055 counts factorizations (multiset partitions of prime indices), strict
A045778.
A050361 counts factorizations into distinct prime powers.
-
prix[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n], {p_,k_}:>Table[PrimePi[p],{k}]]]];
mce[y_]:=Table[ConstantArray[y[[1]],#]&/@ptn, {ptn,IntegerPartitions[Length[y]]}];
Select[Range[100], Select[Join@@@Tuples[mce/@Split[prix[#]]], SameQ@@Total/@#&]!={}&]
A382215
MM-numbers of multiset partitions into constant blocks with a common sum.
Original entry on oeis.org
1, 2, 3, 4, 5, 7, 8, 9, 11, 16, 17, 19, 23, 25, 27, 31, 32, 35, 41, 49, 53, 59, 64, 67, 81, 83, 97, 103, 109, 121, 125, 127, 128, 131, 157, 175, 179, 191, 209, 211, 227, 241, 243, 245, 256, 277, 283, 289, 311, 331, 343, 353, 361, 367, 391, 401, 419, 431, 461
Offset: 1
The terms together with their prime indices of prime indices begin:
1: {}
2: {{}}
3: {{1}}
4: {{},{}}
5: {{2}}
7: {{1,1}}
8: {{},{},{}}
9: {{1},{1}}
11: {{3}}
16: {{},{},{},{}}
17: {{4}}
19: {{1,1,1}}
23: {{2,2}}
25: {{2},{2}}
27: {{1},{1},{1}}
31: {{5}}
32: {{},{},{},{},{}}
35: {{2},{1,1}}
41: {{6}}
49: {{1,1},{1,1}}
53: {{1,1,1,1}}
59: {{7}}
Twice-partitions of this type are counted by
A279789.
Factorizations of this type are counted by
A381995.
For strict blocks and distinct sums we have
A382201, counted by
A381633.
Normal multiset partitions of this type are counted by
A382204.
For strict instead of constant blocks we have
A382304, counted by
A382080.
For sets of constant multisets with distinct sums
A382426, counted by
A381635.
-
prix[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n], {p_,k_}:>Table[PrimePi[p],{k}]]]];
Select[Range[100],SameQ@@Total/@prix/@prix[#] && And@@SameQ@@@prix/@prix[#]&]
-
is(k) = my(f=factor(k)[, 1]~, k, p, v=vector(#f, i, primepi(f[i]))); for(i=1, #v, k=isprimepower(v[i], &p); if(k||v[i]==1, v[i]=k*primepi(p), return(0))); #Set(v)<2; \\ Jinyuan Wang, Apr 02 2025
A383093
Number of integer partitions of n that can be partitioned into constant blocks with a common sum.
Original entry on oeis.org
1, 1, 2, 2, 4, 2, 7, 2, 9, 5, 9, 2, 23, 2, 11, 10, 24, 2, 33, 2, 36, 12, 15, 2, 87, 7, 17, 17, 53, 2, 96, 2, 79, 16, 21, 14, 196, 2, 23, 18, 154, 2, 166, 2, 99, 54, 27, 2, 431, 9, 85, 22, 128, 2, 303, 18, 261, 24, 33, 2, 771, 2, 35, 73, 331, 20, 422, 2, 198, 28, 216, 2, 1369
Offset: 0
The partition (4,4,2,2,2,2,1,1,1,1,1,1,1,1) has two partitions into constant blocks with a common sum: {{4,4},{2,2,2,2},{1,1,1,1,1,1,1,1}} and {{4},{4},{2,2},{2,2},{1,1,1,1},{1,1,1,1}}, so is counted under a(24).
The a(1) = 1 through a(8) = 9 partitions:
(1) (2) (3) (4) (5) (6) (7) (8)
(11) (111) (22) (11111) (33) (1111111) (44)
(211) (222) (422)
(1111) (2211) (2222)
(3111) (22211)
(21111) (41111)
(111111) (221111)
(2111111)
(11111111)
Twice-partitions of this type (constant with common) are counted by
A279789.
Multiset partitions of this type are ranked by
A383309.
Normal multiset partitions of this type are counted by
A382203, sets
A381718.
For distinct instead of equal block-sums we have
A382427.
A050361 counts factorizations into distinct prime powers, see
A381715.
A323774 counts partitions into constant blocks with a common sum
Cf.
A006171,
A047966,
A279784,
A295935,
A323774,
A326534,
A353864,
A355743,
A381716,
A382076,
A382204.
-
mce[y_]:=Table[ConstantArray[y[[1]],#]&/@ptn,{ptn,IntegerPartitions[Length[y]]}];
Table[Length[Select[IntegerPartitions[n],Length[Select[Join@@@Tuples[mce/@Split[#]],SameQ@@Total/@#&]]>0&]],{n,0,30}]
A382301
Number of integer partitions of n having a unique multiset partition into constant blocks with distinct sums.
Original entry on oeis.org
1, 1, 2, 2, 3, 6, 8, 9, 14, 16, 25, 30, 41, 52, 69, 83, 105, 129, 164, 208, 263, 315, 388, 449, 573, 694
Offset: 0
The a(4) = 3 through a(8) = 14 partitions and their unique multiset partition into constant blocks with distinct sums:
{4} {5} {6} {7} {8}
{22} {1}{4} {33} {1}{6} {44}
{1}{3} {2}{3} {1}{5} {2}{5} {1}{7}
{11}{3} {2}{4} {3}{4} {2}{6}
{1}{22} {11}{4} {11}{5} {3}{5}
{2}{111} {11}{22} {1}{33} {11}{6}
{1}{2}{3} {3}{22} {2}{33}
{1}{11}{3} {1}{2}{4} {11}{33}
{3}{1111} {11}{222}
{1}{2}{5}
{1}{3}{4}
{1}{3}{22}
{1}{4}{111}
{1}{111}{22}
For distinct blocks instead of block-sums we have
A000726, ranks
A004709.
Twice-partitions of this type (constant with distinct) are counted by
A279786.
The Heinz numbers of these partitions are
A381991, positions of 1 in
A381635.
Normal multiset partitions of this type are counted by
A382203.
For at least one choice we have
A382427.
A050361 counts factorizations into distinct prime powers.
Cf.
A006171,
A047966,
A279784,
A293511,
A295935,
A353864,
A381633,
A381716,
A381990,
A381992,
A381993,
A382079.
-
hwt[n_]:=Total[Cases[FactorInteger[n],{p_,k_}:>PrimePi[p]*k]];
pfacs[n_]:=If[n<=1,{{}},Join@@Table[(Prepend[#,d]&)/@Select[pfacs[n/d],Min@@#>=d&],{d,Select[Rest[Divisors[n]],PrimePowerQ]}]];
Table[Length[Select[IntegerPartitions[n],Length[Select[pfacs[Times@@Prime/@#],UnsameQ@@hwt/@#&]]==1&]],{n,0,10}]
A382304
MM-numbers of multiset partitions into sets with a common sum.
Original entry on oeis.org
1, 2, 3, 4, 5, 8, 9, 11, 13, 16, 17, 25, 27, 29, 31, 32, 41, 43, 47, 59, 64, 67, 73, 79, 81, 83, 101, 109, 113, 121, 125, 127, 128, 137, 139, 143, 149, 157, 163, 167, 169, 179, 181, 191, 199, 211, 233, 241, 243, 256, 257, 269, 271, 277, 283, 289, 293, 313, 317
Offset: 1
The terms together with their prime indices of prime indices begin:
1: {}
2: {{}}
3: {{1}}
4: {{},{}}
5: {{2}}
8: {{},{},{}}
9: {{1},{1}}
11: {{3}}
13: {{1,2}}
16: {{},{},{},{}}
17: {{4}}
25: {{2},{2}}
27: {{1},{1},{1}}
29: {{1,3}}
31: {{5}}
32: {{},{},{},{},{}}
Set partitions of this type are counted by
A035470.
Twice-partitions of this type are counted by
A279788.
For just strict blocks we have
A302478.
Factorizations of this type are counted by
A382080.
For distinct instead of equal sums we have
A382201.
For constant instead of strict blocks we have
A382215.
Normal multiset partitions of this type are counted by
A382429.
-
prix[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
Select[Range[100],SameQ@@Total/@prix/@prix[#]&&And@@UnsameQ@@@prix/@prix[#]&]
A382427
Number of integer partitions of n that can be partitioned into constant blocks with distinct sums.
Original entry on oeis.org
1, 1, 2, 3, 4, 7, 11, 14, 19, 28, 39, 50, 70, 91, 120, 161, 203, 260, 338, 426, 556, 695, 863, 1082, 1360, 1685
Offset: 0
The partition (3,2,2,2,1) can be partitioned as {{1},{2},{3},{2,2}} or {{1},{3},{2,2,2}}, so is counted under a(10).
The a(1) = 1 through a(7) = 14 partitions:
(1) (2) (3) (4) (5) (6) (7)
(11) (21) (22) (32) (33) (43)
(111) (31) (41) (42) (52)
(1111) (221) (51) (61)
(311) (222) (322)
(2111) (321) (331)
(11111) (411) (421)
(2211) (511)
(3111) (2221)
(21111) (4111)
(111111) (22111)
(31111)
(211111)
(1111111)
Twice-partitions of this type (constant with distinct) are counted by
A279786.
Normal multiset partitions of this type are counted by
A382203, sets
A381718.
A050361 counts factorizations into distinct prime powers.
Cf.
A006171,
A047966,
A279784,
A295935,
A300385,
A353864,
A381633,
A381716,
A381990,
A381993,
A382079,
A382876.
-
hwt[n_]:=Total[Cases[FactorInteger[n],{p_,k_}:>PrimePi[p]*k]];
pfacs[n_]:=If[n<=1,{{}},Join@@Table[(Prepend[#,d]&)/@Select[pfacs[n/d],Min@@#>=d&],{d,Select[Rest[Divisors[n]],PrimePowerQ]}]];
Table[Length[Select[IntegerPartitions[n],Select[pfacs[Times@@Prime/@#],UnsameQ@@hwt/@#&]!={}&]],{n,0,10}]
A381807
Number of multisets that can be obtained by choosing a constant partition of each m = 0..n and taking the multiset union.
Original entry on oeis.org
1, 1, 2, 4, 12, 24, 92, 184, 704, 2016, 7600, 15200, 80664, 161328, 601696, 2198824, 9868544, 19737088, 102010480, 204020960
Offset: 0
The a(1) = 1 through a(4) = 12 multisets:
{1} {1,2} {1,2,3} {1,2,3,4}
{1,1,1} {1,1,1,3} {1,1,1,3,4}
{1,1,1,1,2} {1,2,2,2,3}
{1,1,1,1,1,1} {1,1,1,1,2,4}
{1,1,1,2,2,3}
{1,1,1,1,1,1,4}
{1,1,1,1,1,2,3}
{1,1,1,1,2,2,2}
{1,1,1,1,1,1,1,3}
{1,1,1,1,1,1,2,2}
{1,1,1,1,1,1,1,1,2}
{1,1,1,1,1,1,1,1,1,1}
The number of possible choices was
A066843.
A000688 counts multiset partitions into constant blocks.
A050361 and
A381715 count multiset partitions into constant multisets.
A066723 counts partitions coarser than {1..n}, primorial case of
A317141.
A265947 counts refinement-ordered pairs of integer partitions.
A321470 counts partitions finer than {1..n}, primorial case of
A300383.
Cf.
A001970,
A018818,
A213385,
A299200,
A321467,
A321468,
A321471,
A321514,
A355731,
A381453,
A381455.
-
Table[Length[Union[Sort/@Join@@@Tuples[Select[IntegerPartitions[#],SameQ@@#&]&/@Range[n]]]],{n,0,10}]
A381872
Number of multisets that can be obtained by taking the sum of each block of a multiset partition of the prime indices of n into blocks having a common sum.
Original entry on oeis.org
1, 1, 1, 2, 1, 1, 1, 2, 2, 1, 1, 2, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 2, 1, 2, 1, 1, 1, 3, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 3, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 4, 1, 1, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 2, 1, 1, 1
Offset: 1
The prime indices of 144 are {1,1,1,1,2,2}, with the following 4 multiset partitions having common block sum:
{{1,1,1,1,2,2}}
{{2,2},{1,1,1,1}}
{{1,1,2},{1,1,2}}
{{2},{2},{1,1},{1,1}}
with sums: 8, 4, 4, 2, of which 3 are distinct, so a(144) = 3.
The prime indices of 1296 are {1,1,1,1,2,2,2,2}, with the following 7 multiset partitions having common block sum:
{{1,1,1,1,2,2,2,2}}
{{2,2,2},{1,1,1,1,2}}
{{1,1,2,2},{1,1,2,2}}
{{2,2},{2,2},{1,1,1,1}}
{{2,2},{1,1,2},{1,1,2}}
{{1,2},{1,2},{1,2},{1,2}}
{{2},{2},{2},{2},{1,1},{1,1}}
with sums: 12, 6, 6, 4, 4, 3, 2, of which 5 are distinct, so a(1296) = 5.
With equal blocks instead of sums we have
A089723.
Positions of terms > 1 are
A321454.
With distinct instead of equal sums we have
A381637, before sums
A321469.
A265947 counts refinement-ordered pairs of integer partitions.
Other multiset partitions of prime indices:
-
prix[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[mset_]:=Union[Sort[Sort/@(#/.x_Integer:>mset[[x]])]&/@sps[Range[Length[mset]]]];
Table[Length[Union[Sort[Total/@#]&/@Select[mps[prix[n]],SameQ@@Total/@#&]]],{n,100}]
A382426
MM-numbers of sets of constant multisets with distinct sums.
Original entry on oeis.org
1, 2, 3, 5, 6, 7, 10, 11, 14, 15, 17, 19, 21, 22, 23, 30, 31, 33, 34, 38, 41, 42, 46, 51, 53, 55, 57, 59, 62, 66, 67, 69, 77, 82, 83, 85, 93, 95, 97, 102, 103, 106, 109, 110, 114, 115, 118, 119, 123, 127, 131, 133, 134, 138, 154, 155, 157, 159, 161, 165, 166
Offset: 1
The terms together with their prime indices of prime indices begin:
1: {}
2: {{}}
3: {{1}}
5: {{2}}
6: {{},{1}}
7: {{1,1}}
10: {{},{2}}
11: {{3}}
14: {{},{1,1}}
15: {{1},{2}}
17: {{4}}
19: {{1,1,1}}
21: {{1},{1,1}}
22: {{},{3}}
23: {{2,2}}
30: {{},{1},{2}}
Twice-partitions of this type are counted by
A279786.
For just constant blocks we have
A302492.
For just distinct sums we have
A326535.
Factorizations of this type are counted by
A381635.
For strict instead of constant blocks we have
A382201.
Normal multiset partitions of this type are counted by
A382203.
For equal instead of distinct sums we have
A382215.
Cf.
A000688,
A000720,
A000961,
A302242,
A302494,
A321469,
A326534,
A355743,
A356065,
A381636,
A381716.
-
prix[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
Select[Range[100],UnsameQ@@Total/@prix/@prix[#]&&And@@SameQ@@@prix/@prix[#]&]
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