A324755
Number of integer partitions of n not containing 1 or any part whose prime indices all belong to the partition.
Original entry on oeis.org
1, 0, 1, 1, 2, 1, 4, 3, 5, 6, 10, 7, 16, 14, 23, 23, 35, 34, 53, 54, 75, 80, 112, 115, 160, 169, 223, 244, 315, 339, 442, 478, 604, 664, 832, 910, 1131, 1245, 1524, 1689, 2054, 2263, 2743, 3039, 3634, 4042, 4809, 5343, 6326, 7035, 8276, 9217, 10795, 12011
Offset: 0
The a(2) = 1 through a(10) = 10 integer partitions (A = 10):
(2) (3) (4) (5) (6) (7) (8) (9) (A)
(22) (33) (43) (44) (54) (55)
(42) (52) (62) (63) (64)
(222) (422) (72) (73)
(2222) (333) (82)
(522) (433)
(442)
(622)
(4222)
(22222)
Cf.
A000837,
A001462,
A051424,
A112798,
A276625,
A290822,
A304360,
A306844,
A324695,
A324696,
A324744.
-
Table[Length[Select[IntegerPartitions[n],!MemberQ[#,k_/;SubsetQ[#,PrimePi/@First/@If[k==1,{},FactorInteger[k]]]]&]],{n,0,30}]
A324759
Heinz numbers of integer partitions containing no part > 1 whose prime indices all belong to the partition.
Original entry on oeis.org
1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 13, 16, 17, 19, 20, 21, 22, 23, 25, 26, 27, 29, 31, 32, 33, 34, 35, 37, 39, 40, 41, 43, 44, 46, 47, 49, 50, 51, 52, 53, 57, 58, 59, 61, 62, 63, 64, 65, 67, 68, 71, 73, 74, 77, 79, 80, 81, 82, 83, 85, 86, 87, 88, 89, 91, 92, 93
Offset: 1
The sequence of terms together with their prime indices begins:
1: {}
2: {1}
3: {2}
4: {1,1}
5: {3}
7: {4}
8: {1,1,1}
9: {2,2}
10: {1,3}
11: {5}
13: {6}
16: {1,1,1,1}
17: {7}
19: {8}
20: {1,1,3}
21: {2,4}
22: {1,5}
23: {9}
25: {3,3}
26: {1,6}
The subset version is
A324738, with maximal case
A324744. The strict integer partition version is
A324749. The integer partition version is
A324754. An infinite version is
A324694.
Cf.
A000720,
A001221,
A007097,
A056239,
A112798,
A276625,
A289509,
A290822,
A306844,
A324695,
A324750,
A324755,
A324760.
-
primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
Select[Range[100],!MemberQ[DeleteCases[primeMS[#],1],k_/;SubsetQ[primeMS[#],primeMS[k]]]&]
A324766
Matula-Goebel numbers of recursively anti-transitive rooted trees.
Original entry on oeis.org
1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 16, 17, 19, 20, 21, 22, 23, 25, 27, 29, 31, 32, 33, 34, 35, 40, 44, 46, 49, 50, 51, 53, 57, 59, 62, 63, 64, 67, 68, 71, 73, 77, 79, 80, 81, 83, 85, 87, 88, 92, 93, 95, 97, 99, 100, 103, 109, 115, 118, 121, 124, 125, 127, 128
Offset: 1
The sequence of recursively anti-transitive rooted trees together with their Matula-Goebel numbers begins:
1: o
2: (o)
3: ((o))
4: (oo)
5: (((o)))
7: ((oo))
8: (ooo)
9: ((o)(o))
10: (o((o)))
11: ((((o))))
16: (oooo)
17: (((oo)))
19: ((ooo))
20: (oo((o)))
21: ((o)(oo))
22: (o(((o))))
23: (((o)(o)))
25: (((o))((o)))
27: ((o)(o)(o))
29: ((o((o))))
31: (((((o)))))
32: (ooooo)
33: ((o)(((o))))
34: (o((oo)))
35: (((o))(oo))
40: (ooo((o)))
44: (oo(((o))))
46: (o((o)(o)))
49: ((oo)(oo))
50: (o((o))((o)))
-
primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
totantiQ[n_]:=And[Intersection[Union@@primeMS/@primeMS[n],primeMS[n]]=={},And@@totantiQ/@primeMS[n]];
Select[Range[100],totantiQ]
A324754
Number of integer partitions of n containing no part > 1 whose prime indices all belong to the partition.
Original entry on oeis.org
1, 1, 2, 2, 4, 3, 7, 8, 11, 12, 19, 19, 30, 34, 46, 50, 71, 76, 104, 119, 151, 171, 225, 247, 315, 360, 446, 504, 629, 703, 867, 986, 1192, 1346, 1636, 1837, 2204, 2500, 2965, 3348, 3980, 4475, 5276, 5963, 6973, 7852, 9194, 10335, 12009, 13536, 15650, 17589
Offset: 0
The a(1) = 1 through a(8) = 11 integer partitions:
(1) (2) (3) (4) (5) (6) (7) (8)
(11) (111) (22) (311) (33) (43) (44)
(31) (11111) (42) (52) (62)
(1111) (51) (61) (71)
(222) (331) (422)
(3111) (511) (611)
(111111) (31111) (2222)
(1111111) (3311)
(5111)
(311111)
(11111111)
Cf.
A000837,
A001462,
A007097,
A051424,
A112798,
A276625,
A290822,
A304360,
A306844,
A324695,
A324750,
A324755,
A324760.
-
Table[Length[Select[IntegerPartitions[n],!MemberQ[#,k_/;SubsetQ[#,PrimePi/@First/@FactorInteger[k]]]&]],{n,0,30}]
A324760
Heinz numbers of integer partitions not containing 1 or any part whose prime indices all belong to the partition.
Original entry on oeis.org
1, 3, 5, 7, 9, 11, 13, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 47, 49, 51, 53, 57, 59, 61, 63, 65, 67, 71, 73, 77, 79, 81, 83, 85, 87, 89, 91, 93, 95, 97, 99, 101, 103, 107, 109, 111, 113, 115, 117, 121, 123, 125, 127, 129, 131, 133, 137, 139
Offset: 1
The sequence of terms together with their prime indices begins:
1: {}
3: {2}
5: {3}
7: {4}
9: {2,2}
11: {5}
13: {6}
17: {7}
19: {8}
21: {2,4}
23: {9}
25: {3,3}
27: {2,2,2}
29: {10}
31: {11}
33: {2,5}
35: {3,4}
37: {12}
39: {2,6}
41: {13}
The subset version is
A324739, with maximal case
A324762. The strict integer partition version is
A324750. The integer partition version is
A324755. An infinite version is
A324694.
Cf.
A000720,
A001221,
A007097,
A056239,
A112798,
A289509,
A290822,
A306844,
A324695,
A324696,
A324737,
A324744.
-
primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
Select[Range[100],!MemberQ[primeMS[#],k_/;SubsetQ[primeMS[#],primeMS[k]]]&]
A324762
Number of maximal subsets of {2...n} containing no element whose prime indices all belong to the subset.
Original entry on oeis.org
1, 1, 2, 2, 2, 2, 4, 4, 6, 6, 8, 8, 16, 16, 16, 16, 16, 16, 32, 32, 40, 40, 52, 52, 64, 64, 72, 72, 144, 144, 176, 176, 200, 200, 232, 232, 464, 464, 464, 464, 536, 536, 1072, 1072, 1072, 1072, 2144, 2144, 2400, 2400, 2400, 2400, 4800, 4800, 4800, 4800, 4800
Offset: 1
The a(2) = 1 through a(9) = 6 maximal subsets:
{2} {2} {2,4} {3,4} {3,4,6} {3,4,6} {3,4,6,8} {2,4,5,6,8}
{3} {3,4} {2,4,5} {2,4,5,6} {3,6,7} {3,6,7,8} {2,5,6,7,8}
{2,4,5,6} {2,4,5,6,8} {3,4,6,8,9}
{2,5,6,7} {2,5,6,7,8} {3,6,7,8,9}
{4,5,6,8,9}
{5,6,7,8,9}
The non-maximal version is
A324739.
The version for subsets of {1...n} is
A324744.
-
maxim[s_]:=Complement[s,Last/@Select[Tuples[s,2],UnsameQ@@#&&SubsetQ@@#&]];
Table[Length[maxim[Select[Subsets[Range[2,n]],!MemberQ[#,k_/;SubsetQ[#,PrimePi/@First/@FactorInteger[k]]]&]]],{n,10}]
-
pset(n)={my(b=0, f=factor(n)[, 1]); sum(i=1, #f, 1<<(primepi(f[i])))}
a(n)={my(p=vector(n, k, pset(k)), d=0); for(i=1, #p, d=bitor(d, p[i]));
my(ismax(b)=for(k=1, #p, if(!bittest(b,k) && bitnegimply(p[k], b), my(e=bitor(b, 1<#p, ismax(b), my(f=bitnegimply(p[k], b)); if(!f || bittest(d, k), self()(k+1, b)) + if(f, self()(k+1, b+(1<Andrew Howroyd, Aug 27 2019
A324767
Number of recursively anti-transitive rooted identity trees with n nodes.
Original entry on oeis.org
1, 1, 1, 1, 2, 3, 5, 9, 17, 33, 63, 126, 254, 511, 1039, 2124, 4371, 9059, 18839, 39339, 82385, 173111, 364829, 771010, 1633313
Offset: 1
The a(4) = 1 through a(8) = 9 recursively anti-transitive rooted identity trees:
(((o))) (o((o))) ((o((o)))) (((o((o))))) ((o)(o((o))))
((((o)))) (o(((o)))) ((o)(((o)))) (o((o((o)))))
(((((o))))) ((o(((o))))) ((((o((o))))))
(o((((o))))) (((o)(((o)))))
((((((o)))))) (((o(((o))))))
((o)((((o)))))
((o((((o))))))
(o(((((o))))))
(((((((o)))))))
-
iallt[n_]:=Select[Union[Sort/@Join@@(Tuples[iallt/@#]&/@IntegerPartitions[n-1])],UnsameQ@@#&&Intersection[Union@@#,#]=={}&];
Table[Length[iallt[n]],{n,10}]
A324770
Number of fully anti-transitive rooted identity trees with n nodes.
Original entry on oeis.org
1, 1, 1, 1, 2, 3, 6, 13, 27, 58, 128, 286, 640, 1452, 3308, 7594, 17512, 40591, 94449, 220672
Offset: 1
The a(1) = 1 through a(7) = 6 fully anti-transitive rooted identity trees:
o (o) ((o)) (((o))) ((o(o))) (((o(o)))) ((o(o(o))))
((((o)))) ((o((o)))) ((((o(o)))))
(((((o))))) (((o)((o))))
(((o((o)))))
((o(((o)))))
((((((o))))))
-
idall[n_]:=If[n==1,{{}},Select[Union[Sort/@Join@@(Tuples[idall/@#]&/@IntegerPartitions[n-1])],UnsameQ@@#&]];
Table[Length[Select[idall[n],Intersection[Union@@Rest[FixedPointList[Union@@#&,#]],#]=={}&]],{n,10}]
A331785
Lexicographically earliest sequence containing 1 and all positive integers with exactly one prime index already in the sequence, counting multiplicity.
Original entry on oeis.org
1, 2, 3, 5, 11, 14, 21, 26, 31, 34, 35, 38, 39, 43, 46, 51, 57, 58, 65, 69, 73, 74, 77, 82, 85, 87, 94, 95, 98, 101, 106, 111, 115, 118, 122, 123, 127, 134, 139, 141, 142, 143, 145, 147, 149, 158, 159, 163, 166, 167, 177, 178, 182, 183, 185, 187, 191, 194, 199
Offset: 1
The sequence of terms together with their prime indices begins:
1: {} 73: {21} 142: {1,20} 205: {3,13}
2: {1} 74: {1,12} 143: {5,6} 206: {1,27}
3: {2} 77: {4,5} 145: {3,10} 209: {5,8}
5: {3} 82: {1,13} 147: {2,4,4} 213: {2,20}
11: {5} 85: {3,7} 149: {35} 214: {1,28}
14: {1,4} 87: {2,10} 158: {1,22} 217: {4,11}
21: {2,4} 94: {1,15} 159: {2,16} 218: {1,29}
26: {1,6} 95: {3,8} 163: {38} 226: {1,30}
31: {11} 98: {1,4,4} 166: {1,23} 233: {51}
34: {1,7} 101: {26} 167: {39} 235: {3,15}
35: {3,4} 106: {1,16} 177: {2,17} 237: {2,22}
38: {1,8} 111: {2,12} 178: {1,24} 238: {1,4,7}
39: {2,6} 115: {3,9} 182: {1,4,6} 245: {3,4,4}
43: {14} 118: {1,17} 183: {2,18} 249: {2,23}
46: {1,9} 122: {1,18} 185: {3,12} 253: {5,9}
51: {2,7} 123: {2,13} 187: {5,7} 262: {1,32}
57: {2,8} 127: {31} 191: {43} 265: {3,16}
58: {1,10} 134: {1,19} 194: {1,25} 266: {1,4,8}
65: {3,6} 139: {34} 199: {46} 267: {2,24}
69: {2,9} 141: {2,15} 201: {2,19} 269: {57}
For example, the prime indices of 77 are {4,5}, of which only 5 is in the sequence, so 77 is in the sequence.
Numbers S without all prime indices in S are
A324694.
Numbers S without any prime indices in S are
A324695.
Numbers S with at most one prime index in S are
A331784.
Numbers S with at most one distinct prime index in S are
A331912.
Numbers S with exactly one distinct prime index in S are
A331913.
-
primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
aQ[n_]:=n==1||Length[Select[primeMS[n],aQ]]==1;
Select[Range[100],aQ]
A324739
Number of subsets of {2...n} containing no element whose prime indices all belong to the subset.
Original entry on oeis.org
1, 2, 3, 6, 10, 20, 30, 60, 96, 192, 312, 624, 936, 1872, 3744, 7488, 12480, 24960, 37440, 74880, 142848, 285696, 456192, 912384, 1548288, 3096576, 5308416, 10616832, 15925248, 31850496, 51978240, 103956480, 200835072, 401670144, 771489792, 1542979584, 2314469376
Offset: 1
The a(1) = 1 through a(6) = 20 subsets:
{} {} {} {} {} {}
{2} {2} {2} {2} {2}
{3} {3} {3} {3}
{4} {4} {4}
{2,4} {5} {5}
{3,4} {2,4} {6}
{2,5} {2,4}
{3,4} {2,5}
{4,5} {2,6}
{2,4,5} {3,4}
{3,6}
{4,5}
{4,6}
{5,6}
{2,4,5}
{2,4,6}
{2,5,6}
{3,4,6}
{4,5,6}
{2,4,5,6}
The maximal case is
A324762. The case of subsets of {1...n} is
A324738. The strict integer partition version is
A324750. The integer partition version is
A324755. The Heinz number version is
A324760. An infinite version is
A324694.
Cf.
A000720,
A001221,
A001462,
A007097,
A084422,
A085945,
A112798,
A276625,
A279861,
A290689,
A290822,
A304360,
A306844.
-
Table[Length[Select[Subsets[Range[2,n]],!MemberQ[#,k_/;SubsetQ[#,PrimePi/@First/@FactorInteger[k]]]&]],{n,10}]
-
pset(n)={my(b=0,f=factor(n)[,1]); sum(i=1, #f, 1<<(primepi(f[i])))}
a(n)={my(p=vector(n,k,pset(k)), d=0); for(i=1, #p, d=bitor(d, p[i]));
((k,b)->if(k>#p, 1, my(t=self()(k+1,b)); if(bitnegimply(p[k], b), t+=if(bittest(d,k), self()(k+1, b+(1<Andrew Howroyd, Aug 16 2019
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