A324758
Heinz numbers of integer partitions containing no prime indices of the parts.
Original entry on oeis.org
1, 2, 3, 4, 5, 7, 8, 9, 10, 11, 13, 16, 17, 19, 20, 21, 22, 23, 25, 27, 29, 31, 32, 33, 34, 35, 37, 40, 41, 43, 44, 46, 47, 49, 50, 51, 53, 57, 59, 61, 62, 63, 64, 65, 67, 68, 71, 73, 77, 79, 80, 81, 82, 83, 85, 87, 88, 89, 91, 92, 93, 94, 95, 97, 99, 100, 101
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}
27: {2,2,2}
The subset version is
A324741, with maximal case
A324743. The strict integer partition version is
A324751. The integer partition version is
A324756. An infinite version is
A324695.
Cf.
A000720,
A001221,
A001462,
A007097,
A056239,
A112798,
A276625,
A289509,
A290822,
A304360,
A306844,
A324742,
A324753,
A324764.
-
primeMS[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
Select[Range[100],Intersection[primeMS[#],Union@@primeMS/@primeMS[#]]=={}&]
A324756
Number of integer partitions of n containing no prime indices of the parts.
Original entry on oeis.org
1, 1, 2, 2, 4, 3, 7, 7, 9, 11, 16, 16, 24, 25, 34, 39, 50, 54, 70, 79, 96, 111, 135, 152, 186, 208, 249, 285, 335, 377, 448, 506, 588, 664, 777, 873, 1010, 1139, 1309, 1471, 1697, 1890, 2175, 2435, 2772, 3106, 3532, 3941, 4478, 4995, 5643, 6297, 7107, 7897
Offset: 0
The a(1) = 1 through a(8) = 9 integer partitions:
(1) (2) (3) (4) (5) (6) (7) (8)
(11) (111) (22) (311) (33) (43) (44)
(31) (11111) (42) (52) (71)
(1111) (51) (331) (422)
(222) (511) (2222)
(3111) (31111) (3311)
(111111) (1111111) (5111)
(311111)
(11111111)
Cf.
A000720,
A000837,
A001462,
A051424,
A112798,
A276625,
A304360,
A306844,
A324764,
A324742,
A324753.
-
Table[Length[Select[IntegerPartitions[n],Intersection[#,PrimePi/@First/@Join@@FactorInteger/@#]=={}&]],{n,0,30}]
A324751
Number of strict integer partitions of n containing no prime indices of the parts.
Original entry on oeis.org
1, 1, 1, 1, 2, 1, 3, 3, 2, 4, 5, 5, 6, 8, 8, 12, 10, 14, 13, 18, 19, 26, 25, 30, 34, 39, 40, 51, 55, 60, 71, 77, 90, 97, 111, 123, 136, 153, 170, 179, 216, 230, 264, 282, 322, 345, 385, 423, 470, 513, 573, 629, 686, 755, 834, 910, 1005, 1095, 1194, 1303, 1433
Offset: 0
The a(1) = 1 through a(13) = 8 strict integer partitions (A...D = 10...13):
1 2 3 4 5 6 7 8 9 A B C D
31 42 43 71 54 64 65 75 76
51 52 63 73 83 84 85
72 82 542 93 94
91 731 A2 B2
B1 643
751
931
Cf.
A000720,
A001462,
A007097,
A074971,
A078374,
A112798,
A276625,
A290822,
A305713,
A306844,
A324764.
-
Table[Length[Select[IntegerPartitions[n],UnsameQ@@#&&Intersection[#,PrimePi/@First/@Join@@FactorInteger/@#]=={}&]],{n,0,30}]
A324741
Number of subsets of {1...n} containing no prime indices of the elements.
Original entry on oeis.org
1, 2, 3, 5, 8, 13, 19, 30, 54, 96, 156, 248, 440, 688, 1120, 1864, 3664, 5856, 11232, 16896, 31296, 53952, 91008, 137472, 270528, 516720, 863088, 1710816, 3173856, 4836672, 9329472, 14897376, 29788128, 52256448, 88429248, 166037184, 331648704, 497685888, 829449600
Offset: 0
The a(0) = 1 through a(6) = 19 subsets:
{} {} {} {} {} {} {}
{1} {1} {1} {1} {1} {1}
{2} {2} {2} {2} {2}
{3} {3} {3} {3}
{1,3} {4} {4} {4}
{1,3} {5} {5}
{2,4} {1,3} {6}
{3,4} {1,5} {1,3}
{2,4} {1,5}
{2,5} {2,4}
{3,4} {2,5}
{4,5} {3,4}
{2,4,5} {3,6}
{4,5}
{4,6}
{5,6}
{2,4,5}
{3,4,6}
{4,5,6}
An example for n = 20 is {5,6,7,9,10,12,14,15,16,19,20}, with prime indices:
5: {3}
6: {1,2}
7: {4}
9: {2,2}
10: {1,3}
12: {1,1,2}
14: {1,4}
15: {2,3}
16: {1,1,1,1}
19: {8}
20: {1,1,3}
None of these prime indices {1,2,3,4,8} belong to the subset, as required.
The maximal case is
A324743. The strict integer partition version is
A324751. The integer partition version is
A324756. The Heinz number version is
A324758. An infinite version is
A304360.
Cf.
A000720,
A001462,
A007097,
A076078,
A084422,
A112798,
A276625,
A279861,
A290689,
A290822,
A304360,
A306844.
-
Table[Length[Select[Subsets[Range[n]],Intersection[#,PrimePi/@First/@Join@@FactorInteger/@#]=={}&]],{n,0,10}]
-
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(!bitand(p[k], b), t+=if(bittest(d,k), self()(k+1, b+(1<Andrew Howroyd, Aug 16 2019
A324743
Number of maximal subsets of {1...n} containing no prime indices of the elements.
Original entry on oeis.org
1, 1, 2, 2, 3, 4, 5, 8, 8, 8, 8, 12, 12, 18, 18, 19, 19, 30, 30, 54, 54, 54, 54, 96, 96, 96, 96, 96, 96, 156, 156, 244, 244, 248, 248, 248, 248, 440, 440, 440, 440, 688, 688, 1120, 1120, 1120, 1120, 1864, 1864, 1864, 1864, 1864, 1864, 3664, 3664, 3664, 3664, 3664
Offset: 0
The a(0) = 1 through a(8) = 8 maximal subsets:
{} {1} {1} {2} {1,3} {1,3} {1,3} {1,3,7} {1,3,7}
{2} {1,3} {2,4} {1,5} {1,5} {1,5,7} {1,5,7}
{3,4} {3,4} {2,4,5} {2,4,5} {2,4,5,8}
{2,4,5} {3,4,6} {2,5,7} {2,5,7,8}
{4,5,6} {3,4,6} {3,4,6,8}
{3,6,7} {3,6,7,8}
{4,5,6} {4,5,6,8}
{5,6,7} {5,6,7,8}
An example for n = 15 is {1,5,7,9,13,15}, with prime indices:
1: {}
5: {3}
7: {4}
9: {2,2}
13: {6}
15: {2,3}
None of these prime indices {2,3,4,6} belong to the subset, as required.
The non-maximal case is
A324741. The case for subsets of {2...n} is
A324763.
Cf.
A000720,
A001462,
A007097,
A084422,
A085945,
A112798,
A276625,
A290689,
A290822,
A304360,
A306844,
A320426,
A324764.
-
maxim[s_]:=Complement[s,Last/@Select[Tuples[s,2],UnsameQ@@#&&SubsetQ@@#&]];
Table[Length[maxim[Select[Subsets[Range[n]],Intersection[#,PrimePi/@First/@Join@@FactorInteger/@#]=={}&]]],{n,0,10}]
-
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)=my(e=0); forstep(k=#p, 1, -1, if(bittest(b,k), e=bitor(e,p[k]), if(!bittest(e,k) && !bitand(p[k], b), return(0)) )); 1);
((k, b)->if(k>#p, ismax(b), my(f=!bitand(p[k], b)); if(!f || bittest(d, k), self()(k+1, b)) + if(f, self()(k+1, b+(1<Andrew Howroyd, Aug 26 2019
A324763
Number of maximal subsets of {2...n} containing no prime indices of the elements.
Original entry on oeis.org
1, 1, 2, 2, 2, 3, 6, 6, 6, 6, 10, 10, 16, 16, 16, 16, 24, 24, 48, 48, 48, 48, 84, 84, 84, 84, 84, 84, 144, 144, 228, 228, 228, 228, 228, 228, 420, 420, 420, 420, 648, 648, 1080, 1080, 1080, 1080, 1800, 1800, 1800, 1800, 1800, 1800, 3600, 3600, 3600, 3600, 3600
Offset: 1
The a(1) = 1 through a(9) = 6 subsets:
{} {2} {2} {2,4} {3,4} {2,4,5} {2,4,5} {2,4,5,8} {2,4,5,8}
{3} {3,4} {2,4,5} {3,4,6} {2,5,7} {2,5,7,8} {2,5,7,8}
{4,5,6} {3,4,6} {3,4,6,8} {3,4,6,8,9}
{3,6,7} {3,6,7,8} {3,6,7,8,9}
{4,5,6} {4,5,6,8} {4,5,6,8,9}
{5,6,7} {5,6,7,8} {5,6,7,8,9}
The non-maximal version is
A324742.
The version for subsets of {1...n} is
A324741.
-
maxim[s_]:=Complement[s,Last/@Select[Tuples[s,2],UnsameQ@@#&&SubsetQ@@#&]];
Table[Length[maxim[Select[Subsets[Range[2,n]],Intersection[#,PrimePi/@First/@Join@@FactorInteger/@#]=={}&]]],{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-1, k, pset(k+1)>>1), d=0); for(i=1, #p, d=bitor(d, p[i]));
my(ismax(b)=my(e=0); forstep(k=#p, 1, -1, if(bittest(b,k), e=bitor(e,p[k]), if(!bittest(e,k) && !bitand(p[k], b), return(0)) )); 1);
((k, b)->if(k>#p, ismax(b), my(f=!bitand(p[k], b)); if(!f || bittest(d, k), self()(k+1, b)) + if(f, self()(k+1, b+(1<Andrew Howroyd, Aug 26 2019
A324750
Number of strict 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, 1, 1, 2, 3, 2, 4, 4, 4, 6, 8, 8, 11, 10, 15, 16, 19, 23, 27, 28, 35, 39, 47, 50, 63, 68, 77, 91, 102, 114, 130, 147, 169, 187, 213, 237, 268, 300, 336, 380, 422, 472, 525, 587, 647, 731, 810, 895, 996, 1102, 1227, 1355, 1498, 1661, 1818, 2020, 2221
Offset: 0
The a(2) = 1 through a(17) = 15 strict integer partitions (A...H = 10...17):
2 3 4 5 6 7 8 9 A B C D E F G H
42 43 62 54 64 65 75 76 86 87 97 98
52 63 73 83 84 85 95 96 A6 A7
72 82 542 93 94 A4 A5 C4 B6
A2 A3 B3 B4 D3 C5
642 B2 C2 C3 E2 D4
643 752 D2 763 E3
652 842 654 862 F2
762 943 854
843 A42 863
852 872
A43
A52
B42
6542
Cf.
A000720,
A001462,
A007097,
A074971,
A078374,
A112798,
A276625,
A290822,
A304360,
A305713,
A306844.
-
Table[Length[Select[IntegerPartitions[n],UnsameQ@@#&&!MemberQ[#,1]&&!MemberQ[#,k_/;SubsetQ[#,PrimePi/@First/@FactorInteger[k]]]&]],{n,0,30}]
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
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
A324752
Number of strict integer partitions of n not containing 1 or any prime indices of the parts.
Original entry on oeis.org
1, 0, 1, 1, 1, 1, 2, 3, 1, 4, 4, 4, 5, 6, 7, 10, 9, 12, 12, 16, 17, 22, 22, 26, 31, 35, 37, 46, 50, 55, 66, 70, 82, 90, 101, 114, 127, 143, 159, 172, 202, 215, 246, 267, 301, 327, 366, 402, 447, 491, 545, 600, 655, 722, 795, 875, 964, 1050, 1152, 1259, 1383
Offset: 0
The a(2) = 1 through a(17) = 12 strict integer partitions (A...H = 10...17):
2 3 4 5 6 7 8 9 A B C D E F G H
42 43 54 64 65 75 76 86 87 97 98
52 63 73 83 84 85 95 96 A6 A7
72 82 542 93 94 A4 A5 C4 B6
A2 B2 B3 B4 D3 C5
643 752 C3 E2 D4
842 D2 763 E3
654 943 854
843 A42 863
852 872
A52
B42
An example for n = 60 is (19,14,13,7,5,2), with prime indices:
19: {8}
14: {1,4}
13: {6}
7: {4}
5: {3}
2: {1}
None of these prime indices {1,3,4,6,8} belong to the partition, as required.
Cf.
A000720,
A001462,
A007097,
A074971,
A078374,
A112798,
A276625,
A290822,
A305713,
A306844,
A324764.
-
Table[Length[Select[IntegerPartitions[n],UnsameQ@@#&&!MemberQ[#,1]&&Intersection[#,PrimePi/@First/@Join@@FactorInteger/@#]=={}&]],{n,0,30}]
Showing 1-10 of 12 results.
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