A330233
Least MM-numbers of multisets of multisets with a given number of distinct representatives (obtainable by vertex-permutations).
Original entry on oeis.org
1, 35, 141, 1713, 28011, 355, 34567, 4045, 54849, 64615, 15265, 95363, 126841
Offset: 1
The sequence of terms together with their corresponding multisets of multisets begins:
1: {}
35: {{2},{1,1}}
141: {{1},{2,3}}
355: {{2},{1,1,3}}
1713: {{1},{2,3,4}}
4045: {{2},{1,1,3,4}}
15265: {{2},{1,4},{1,1,3}}
28011: {{1},{2,3,4,5}}
34567: {{1,2},{3,4,5}}
54849: {{1},{2,3},{4,5}}
64615: {{2},{1,1,3,4,5}}
95363: {{2,3},{1,1,4,5}}
126841: {{3},{1,2},{1,4,5}}
Sorted positions of first appearances in
A330098.
MM-numbers of achiral multisets of multisets are
A330232.
MM-numbers of fully-chiral multisets of multisets are
A330236.
Cf.
A001055,
A003238,
A007716,
A056239,
A112798,
A302242,
A303975,
A322847,
A330103,
A330223,
A330227,
A330231.
-
primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
graprms[m_]:=Union[Table[Sort[Sort/@(m/.Apply[Rule,Table[{p[[i]],i},{i,Length[p]}],{1}])],{p,Permutations[Union@@m]}]];
dv=Table[Length[graprms[primeMS/@primeMS[n]]],{n,1000}];
Table[Position[dv,i][[1,1]],{i,First/@Gather[dv]}]
A371127
Powers of 2 times powers > 1 of a prime-indexed prime number.
Original entry on oeis.org
3, 5, 6, 9, 10, 11, 12, 17, 18, 20, 22, 24, 25, 27, 31, 34, 36, 40, 41, 44, 48, 50, 54, 59, 62, 67, 68, 72, 80, 81, 82, 83, 88, 96, 100, 108, 109, 118, 121, 124, 125, 127, 134, 136, 144, 157, 160, 162, 164, 166, 176, 179, 191, 192, 200, 211, 216, 218, 236, 241
Offset: 1
The terms together with their prime indices begin:
3: {2}
5: {3}
6: {1,2}
9: {2,2}
10: {1,3}
11: {5}
12: {1,1,2}
17: {7}
18: {1,2,2}
20: {1,1,3}
22: {1,5}
24: {1,1,1,2}
25: {3,3}
27: {2,2,2}
31: {11}
34: {1,7}
36: {1,1,2,2}
Subset of
A336101 = powers of 2 times powers of primes.
Counting prime factors instead of divisors gives
A371287.
A001221 counts distinct prime factors.
A003963 gives product of prime indices.
A076610 lists products of primes of prime index.
A355731 counts choices of a divisor of each prime index, firsts
A355732.
A355741 counts choices of a prime factor of each prime index.
A371178
Number of integer partitions of n containing all divisors of all parts.
Original entry on oeis.org
1, 1, 1, 2, 3, 4, 6, 9, 12, 16, 21, 28, 37, 48, 62, 80, 101, 127, 162, 202, 252, 312, 386, 475, 585, 713, 869, 1056, 1278, 1541, 1859, 2232, 2675, 3196, 3811, 4534, 5386, 6379, 7547, 8908, 10497, 12345, 14501, 16999, 19897, 23253, 27135, 31618, 36796, 42756
Offset: 0
The partition (4,2,1,1) contains all distinct divisors {1,2,4}, so is counted under a(8).
The partition (4,4,3,2,2,2,1) contains all distinct divisors {1,2,3,4} so is counted under 4 + 4 + 3 + 2 + 2 + 2 + 1 = 18. - _David A. Corneth_, Mar 18 2024
The a(0) = 1 through a(8) = 12 partitions:
() (1) (11) (21) (31) (221) (51) (331) (71)
(111) (211) (311) (321) (421) (521)
(1111) (2111) (2211) (511) (3221)
(11111) (3111) (2221) (3311)
(21111) (3211) (4211)
(111111) (22111) (5111)
(31111) (22211)
(211111) (32111)
(1111111) (221111)
(311111)
(2111111)
(11111111)
For partitions with no divisors of parts we have
A305148, ranks
A316476.
The complement is counted by
A371132.
For submultisets instead of distinct parts we have
A371172, ranks
A371165.
These partitions have ranks
A371177.
A008284 counts partitions by length.
Cf.
A000837,
A003963,
A239312,
A285573,
A305148,
A319055,
A355529,
A370803,
A370808,
A370813,
A371168,
A371171,
A371173.
-
Table[Length[Select[IntegerPartitions[n],SubsetQ[#,Union@@Divisors/@#]&]],{n,0,30}]
A371170
Positive integers with at most as many prime factors (A001222) as distinct divisors of prime indices (A370820).
Original entry on oeis.org
1, 2, 3, 5, 6, 7, 9, 10, 11, 13, 14, 15, 17, 19, 21, 22, 23, 25, 26, 28, 29, 30, 31, 33, 34, 35, 37, 38, 39, 41, 42, 43, 45, 46, 47, 49, 51, 52, 53, 55, 57, 58, 59, 61, 62, 63, 65, 66, 67, 69, 70, 71, 73, 74, 75, 76, 77, 78, 79, 82, 83, 85, 86, 87, 89, 91, 92
Offset: 1
The prime indices of 105 are {2,3,4}, and there are 3 prime factors (3,5,7) and 4 distinct divisors of prime indices (1,2,3,4), so 105 is in the sequence.
The terms together with their prime indices begin:
1: {} 22: {1,5} 42: {1,2,4} 63: {2,2,4}
2: {1} 23: {9} 43: {14} 65: {3,6}
3: {2} 25: {3,3} 45: {2,2,3} 66: {1,2,5}
5: {3} 26: {1,6} 46: {1,9} 67: {19}
6: {1,2} 28: {1,1,4} 47: {15} 69: {2,9}
7: {4} 29: {10} 49: {4,4} 70: {1,3,4}
9: {2,2} 30: {1,2,3} 51: {2,7} 71: {20}
10: {1,3} 31: {11} 52: {1,1,6} 73: {21}
11: {5} 33: {2,5} 53: {16} 74: {1,12}
13: {6} 34: {1,7} 55: {3,5} 75: {2,3,3}
14: {1,4} 35: {3,4} 57: {2,8} 76: {1,1,8}
15: {2,3} 37: {12} 58: {1,10} 77: {4,5}
17: {7} 38: {1,8} 59: {17} 78: {1,2,6}
19: {8} 39: {2,6} 61: {18} 79: {22}
21: {2,4} 41: {13} 62: {1,11} 82: {1,13}
A001221 counts distinct prime factors.
A355731 counts choices of a divisor of each prime index, firsts
A355732.
-
Select[Range[100],PrimeOmega[#]<=Length[Union @@ Divisors/@PrimePi/@First/@If[#==1,{},FactorInteger[#]]]&]
A340652
Number of non-isomorphic twice-balanced multiset partitions of weight n.
Original entry on oeis.org
1, 1, 0, 2, 3, 6, 20, 65, 134, 482, 1562, 4974, 15466, 51768, 179055, 631737, 2216757, 7905325, 28768472, 106852116, 402255207, 1532029660, 5902839974, 23041880550, 91129833143, 364957188701, 1478719359501, 6058859894440, 25100003070184, 105123020009481, 445036528737301
Offset: 0
Non-isomorphic representatives of the a(1) = 1 through a(5) = 6 multiset partitions (empty column indicated by dot):
{{1}} . {{1},{2,2}} {{1,1},{2,2}} {{1},{1},{2,3,3}}
{{2},{1,2}} {{1,2},{1,2}} {{1},{2},{2,3,3}}
{{1,2},{2,2}} {{1},{2},{3,3,3}}
{{1},{3},{2,3,3}}
{{2},{3},{1,2,3}}
{{3},{3},{1,2,3}}
The co-balanced version is
A319616.
The singly balanced version is
A340600.
The cross-balanced version is
A340651.
The version for factorizations is
A340655.
A007716 counts non-isomorphic multiset partitions.
A007718 counts non-isomorphic connected multiset partitions.
A303975 counts distinct prime factors in prime indices.
A316980 counts non-isomorphic strict multiset partitions.
Other balance-related sequences:
-
A047993 counts balanced partitions.
-
A340596 counts co-balanced factorizations.
-
A340653 counts balanced factorizations.
-
A340657/
A340656 list numbers with/without a twice-balanced factorization.
-
EulerT(v)={Vec(exp(x*Ser(dirmul(v, vector(#v, n, 1/n))))-1, -#v)}
permcount(v) = {my(m=1, s=0, k=0, t); for(i=1, #v, t=v[i]; k=if(i>1&&t==v[i-1], k+1, 1); m*=t*k; s+=t); s!/m}
K(q, t, k)={EulerT(Vec(sum(j=1, #q, my(g=gcd(t, q[j])); g*x^(q[j]/g)) + O(x*x^k), -k))}
G(m,n,k,y=1)={my(s=0); forpart(q=m, s+=permcount(q)*exp(sum(t=1, n, y^t*subst(x*Polrev(K(q, t, min(k,n\t))), x, x^t)/t, O(x*x^n)))); s/m!}
seq(n)={Vec(1 + sum(k=1,n, polcoef(G(k,n,k,y) - G(k-1,n,k,y) - G(k,n,k-1,y) + G(k-1,n,k-1,y), k, y)))} \\ Andrew Howroyd, Jan 15 2024
A371169
Positive integers with at least as many prime factors (A001222) as distinct divisors of prime indices (A370820).
Original entry on oeis.org
1, 2, 4, 6, 8, 9, 10, 12, 16, 18, 20, 22, 24, 25, 27, 28, 30, 32, 34, 36, 40, 42, 44, 45, 48, 50, 54, 56, 60, 62, 63, 64, 66, 68, 72, 75, 80, 81, 82, 84, 88, 90, 92, 96, 98, 99, 100, 102, 104, 108, 110, 112, 118, 120, 121, 124, 125, 126, 128, 132, 134, 135
Offset: 1
The terms together with their prime indices begin:
1: {}
2: {1}
4: {1,1}
6: {1,2}
8: {1,1,1}
9: {2,2}
10: {1,3}
12: {1,1,2}
16: {1,1,1,1}
18: {1,2,2}
20: {1,1,3}
22: {1,5}
24: {1,1,1,2}
25: {3,3}
27: {2,2,2}
28: {1,1,4}
30: {1,2,3}
32: {1,1,1,1,1}
34: {1,7}
36: {1,1,2,2}
The version for prime factors instead of divisors on the RHS is
A319899.
A001221 counts distinct prime factors.
A355731 counts choices of a divisor of each prime index, firsts
A355732.
-
Select[Range[100],PrimeOmega[#]>=Length[Union @@ Divisors/@PrimePi/@First/@If[#==1,{},FactorInteger[#]]]&]
A371166
Positive integers with fewer divisors (A000005) than distinct divisors of prime indices (A370820).
Original entry on oeis.org
7, 13, 19, 23, 29, 37, 43, 47, 53, 61, 71, 73, 74, 79, 89, 91, 95, 97, 101, 103, 106, 107, 111, 113, 122, 131, 137, 139, 141, 142, 143, 145, 149, 151, 159, 161, 163, 167, 169, 173, 178, 181, 183, 185, 193, 197, 199, 203, 209, 213, 214, 215, 219, 221, 223, 226
Offset: 1
The terms together with their prime indices begin:
7: {4} 101: {26} 163: {38} 223: {48}
13: {6} 103: {27} 167: {39} 226: {1,30}
19: {8} 106: {1,16} 169: {6,6} 227: {49}
23: {9} 107: {28} 173: {40} 229: {50}
29: {10} 111: {2,12} 178: {1,24} 233: {51}
37: {12} 113: {30} 181: {42} 239: {52}
43: {14} 122: {1,18} 183: {2,18} 247: {6,8}
47: {15} 131: {32} 185: {3,12} 251: {54}
53: {16} 137: {33} 193: {44} 257: {55}
61: {18} 139: {34} 197: {45} 259: {4,12}
71: {20} 141: {2,15} 199: {46} 262: {1,32}
73: {21} 142: {1,20} 203: {4,10} 263: {56}
74: {1,12} 143: {5,6} 209: {5,8} 265: {3,16}
79: {22} 145: {3,10} 213: {2,20} 267: {2,24}
89: {24} 149: {35} 214: {1,28} 269: {57}
91: {4,6} 151: {36} 215: {3,14} 271: {58}
95: {3,8} 159: {2,16} 219: {2,21} 281: {60}
97: {25} 161: {4,9} 221: {6,7} 293: {62}
For (equal to) instead of (less than) we have
A371165, counted by
A371172.
For (greater than) instead of (less than) we have
A371167.
A001221 counts distinct prime factors.
A355731 counts choices of a divisor of each prime index, firsts
A355732.
A371131
Least number with exactly n distinct divisors of prime indices. Position of first appearance of n in A370820.
Original entry on oeis.org
1, 2, 3, 7, 13, 53, 37, 311, 89, 151, 223, 2045, 281, 3241, 1163, 827, 659, 9037, 1069, 17611, 1511, 4211, 28181, 122119, 2423, 10627, 88483, 6997, 7561, 98965, 5443, 88099, 6473, 95603, 309073, 50543, 10271, 192709, 508051, 438979, 14323, 305107, 26203
Offset: 0
The terms together with their prime indices begin:
1: {}
2: {1}
3: {2}
7: {4}
13: {6}
53: {16}
37: {12}
311: {64}
89: {24}
151: {36}
223: {48}
2045: {3,80}
281: {60}
3241: {4,90}
1163: {192}
827: {144}
659: {120}
9037: {4,210}
1069: {180}
17611: {5,252}
Counting prime factors instead of divisors (see
A303975) gives
A062447(>0).
A001221 counts distinct prime factors.
A003963 gives product of prime indices.
A355731 counts choices of a divisor of each prime index, firsts
A355732.
A355741 counts choices of a prime factor of each prime index.
Cf.
A000720,
A000792,
A005179,
A007416,
A355739,
A370348,
A370802,
A370808,
A371130,
A371165,
A371177.
-
rnnm[q_]:=Max@@Select[Range[Min@@q,Max@@q],SubsetQ[q,Range[#]]&];
posfirsts[q_]:=Table[Position[q,n][[1,1]],{n,Min@@q,rnnm[q]}];
posfirsts[Table[Length[Union @@ Divisors/@PrimePi/@First/@If[n==1, {},FactorInteger[n]]],{n,1000}]]
-
f(n) = my(list=List(), f=factor(n)); for (i=1, #f~, fordiv(primepi(f[i,1]), d, listput(list, d))); #Set(list); \\ A370820
a(n) = my(k=1); while (f(k) != n, k++); k; \\ Michel Marcus, May 02 2024
A371132
Number of integer partitions of n with fewer distinct parts than distinct divisors of parts.
Original entry on oeis.org
0, 0, 1, 1, 2, 3, 5, 6, 10, 14, 21, 28, 40, 53, 73, 96, 130, 170, 223, 288, 375, 480, 616, 780, 990, 1245, 1567, 1954, 2440, 3024, 3745, 4610, 5674, 6947, 8499, 10349, 12591, 15258, 18468, 22277, 26841, 32238, 38673, 46262, 55278, 65881, 78423, 93136, 110477
Offset: 0
The partition (4,3,1,1) has 3 distinct parts {1,3,4} and 4 distinct divisors of parts {1,2,3,4}, so is counted under a(9).
The a(0) = 0 through a(9) = 14 partitions:
. . (2) (3) (4) (5) (6) (7) (8) (9)
(22) (32) (33) (43) (44) (54)
(41) (42) (52) (53) (63)
(222) (61) (62) (72)
(411) (322) (332) (81)
(4111) (422) (333)
(431) (432)
(611) (441)
(2222) (522)
(41111) (621)
(3222)
(4311)
(6111)
(411111)
The complement counting all parts on the LHS is
A371172, ranks
A371165.
These partitions are ranked by
A371179.
A008284 counts partitions by length.
-
Table[Length[Select[IntegerPartitions[n],Length[Union[#]] < Length[Union@@Divisors/@#]&]],{n,0,30}]
A371167
Positive integers with more divisors (A000005) than distinct divisors of prime indices (A370820).
Original entry on oeis.org
1, 2, 4, 6, 8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 22, 24, 25, 27, 28, 30, 32, 33, 34, 36, 40, 42, 44, 45, 46, 48, 50, 51, 52, 54, 55, 56, 60, 62, 63, 64, 66, 68, 70, 72, 75, 76, 78, 80, 81, 82, 84, 85, 88, 90, 92, 93, 96, 98, 99, 100, 102, 104, 105, 108, 110
Offset: 1
The prime indices of 814 are {1,5,12}, and there are 8 divisors (1,2,11,22,37,74,407,814) and 7 distinct divisors of prime indices (1,2,3,4,5,6,12), so 814 is in the sequence.
The prime indices of 1859 are {5,6,6}, and there are 6 divisors (1,11,13,143,169,1859) and 5 distinct divisors of prime indices (1,2,3,5,6), so 1859 is in the sequence.
The terms together with their prime indices begin:
1: {}
2: {1}
4: {1,1}
6: {1,2}
8: {1,1,1}
9: {2,2}
10: {1,3}
12: {1,1,2}
14: {1,4}
15: {2,3}
16: {1,1,1,1}
18: {1,2,2}
20: {1,1,3}
21: {2,4}
22: {1,5}
24: {1,1,1,2}
25: {3,3}
27: {2,2,2}
28: {1,1,4}
30: {1,2,3}
For (equal to) instead of (greater than) we get
A371165, counted by
A371172.
For (less than) instead of (greater than) we get
A371166.
A001221 counts distinct prime factors.
A355731 counts choices of a divisor of each prime index, firsts
A355732.
-
Select[Range[100],Length[Divisors[#]]>Length[Union @@ Divisors/@PrimePi/@First/@If[#==1,{},FactorInteger[#]]]&]
Comments