A329139
Numbers whose prime signature is an aperiodic word.
Original entry on oeis.org
1, 2, 3, 4, 5, 7, 8, 9, 11, 12, 13, 16, 17, 18, 19, 20, 23, 24, 25, 27, 28, 29, 31, 32, 37, 40, 41, 43, 44, 45, 47, 48, 49, 50, 52, 53, 54, 56, 59, 60, 61, 63, 64, 67, 68, 71, 72, 73, 75, 76, 79, 80, 81, 83, 84, 88, 89, 90, 92, 96, 97, 98, 99, 101, 103, 104
Offset: 1
The sequence of terms together with their prime signatures begins:
1: ()
2: (1)
3: (1)
4: (2)
5: (1)
7: (1)
8: (3)
9: (2)
11: (1)
12: (2,1)
13: (1)
16: (4)
17: (1)
18: (1,2)
19: (1)
20: (2,1)
23: (1)
24: (3,1)
25: (2)
27: (3)
Aperiodic compositions are
A000740.
Aperiodic binary words are
A027375.
Numbers whose binary expansion is aperiodic are
A328594.
Numbers whose prime signature is a Lyndon word are
A329131.
Numbers whose prime signature is a necklace are
A329138.
Cf.
A025487,
A097318,
A112798,
A124010,
A178472,
A181819,
A304678,
A329133,
A329135,
A329136,
A329137,
A329142.
-
aperQ[q_]:=Array[RotateRight[q,#1]&,Length[q],1,UnsameQ];
Select[Range[100],aperQ[Last/@FactorInteger[#]]&]
A325337
Numbers whose prime exponents are distinct and cover an initial interval of positive integers.
Original entry on oeis.org
1, 2, 3, 5, 7, 11, 12, 13, 17, 18, 19, 20, 23, 28, 29, 31, 37, 41, 43, 44, 45, 47, 50, 52, 53, 59, 61, 63, 67, 68, 71, 73, 75, 76, 79, 83, 89, 92, 97, 98, 99, 101, 103, 107, 109, 113, 116, 117, 124, 127, 131, 137, 139, 147, 148, 149, 151, 153, 157, 163, 164
Offset: 1
The sequence of terms together with their prime indices begins:
1: {}
2: {1}
3: {2}
5: {3}
7: {4}
11: {5}
12: {1,1,2}
13: {6}
17: {7}
18: {1,2,2}
19: {8}
20: {1,1,3}
23: {9}
28: {1,1,4}
29: {10}
31: {11}
37: {12}
41: {13}
43: {14}
44: {1,1,5}
A325369
Numbers with no two prime exponents appearing the same number of times in the prime signature.
Original entry on oeis.org
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 13, 14, 15, 16, 17, 19, 21, 22, 23, 25, 26, 27, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 41, 42, 43, 46, 47, 49, 51, 53, 55, 57, 58, 59, 60, 61, 62, 64, 65, 66, 67, 69, 70, 71, 73, 74, 77, 78, 79, 81, 82, 83, 84, 85, 86
Offset: 1
Most small numbers are in the sequence. However the sequence of non-terms together with their prime indices begins:
12: {1,1,2}
18: {1,2,2}
20: {1,1,3}
24: {1,1,1,2}
28: {1,1,4}
40: {1,1,1,3}
44: {1,1,5}
45: {2,2,3}
48: {1,1,1,1,2}
50: {1,3,3}
52: {1,1,6}
54: {1,2,2,2}
56: {1,1,1,4}
63: {2,2,4}
68: {1,1,7}
72: {1,1,1,2,2}
75: {2,3,3}
76: {1,1,8}
80: {1,1,1,1,3}
88: {1,1,1,5}
For example, the prime indices of 1260 are {1,1,2,2,3,4}, whose multiplicities give the prime signature {1,1,2,2}, and since 1 and 2 appear the same number of times, 1260 is not in the sequence.
Cf.
A056239,
A098859,
A112798,
A118914,
A130091,
A317090,
A319161,
A325326,
A325329,
A325331,
A325337,
A325370,
A325371.
A325330
Number of integer partitions of n whose multiplicities have multiplicities that cover an initial interval of positive integers.
Original entry on oeis.org
1, 1, 2, 2, 4, 5, 7, 11, 16, 22, 31, 44, 55, 77, 96, 127, 158, 208, 251, 329, 400, 501, 610, 766, 915, 1141, 1368, 1677, 2005, 2454, 2913, 3553, 4219, 5110, 6053, 7300, 8644, 10376, 12238, 14645, 17216, 20504, 24047, 28501, 33336, 39373, 45871, 53926, 62745
Offset: 0
The a(0) = 1 through a(8) = 16 partitions:
() (1) (2) (3) (4) (5) (6) (7) (8)
(11) (111) (22) (221) (33) (322) (44)
(211) (311) (222) (331) (332)
(1111) (2111) (411) (511) (422)
(11111) (3111) (2221) (611)
(21111) (3211) (2222)
(111111) (4111) (3221)
(22111) (4211)
(31111) (5111)
(211111) (22211)
(1111111) (32111)
(41111)
(221111)
(311111)
(2111111)
(11111111)
For example, the partition (5,5,4,3,3,3,2,2) has multiplicities (2,1,3,2) with multiplicities (1,2,1) which cover the initial interval {1,2}, so (5,5,4,3,3,3,2,2) is counted under a(27).
Cf.
A000837,
A055932,
A317081,
A317088,
A317089,
A317090,
A317245,
A320348,
A325331,
A325333,
A325337,
A325370.
-
normQ[m_]:=Or[m=={},Union[m]==Range[Max[m]]];
Table[Length[Select[IntegerPartitions[n],normQ[Length/@Split[Sort[Length/@Split[#]]]]&]],{n,0,30}]
A325331
Number of integer partitions of n whose multiplicities appear with distinct multiplicities that cover an initial interval of positive integers.
Original entry on oeis.org
1, 1, 2, 2, 3, 2, 4, 3, 7, 10, 14, 18, 30, 34, 44, 65, 73, 88, 110, 127, 155, 183, 202, 231, 277, 301, 339, 382, 430, 461, 551, 579, 681, 762, 896, 1010, 1255, 1406, 1752, 2061, 2555, 3001, 3783, 4437, 5512, 6611, 8056, 9539, 11668, 13692, 16515, 19435, 23098
Offset: 0
The a(0) = 1 through a(8) = 7 partitions:
() (1) (2) (3) (4) (5) (6) (7) (8)
(11) (111) (22) (11111) (33) (3211) (44)
(1111) (222) (1111111) (2222)
(111111) (3221)
(4211)
(32111)
(11111111)
For example, the partition p = (5,5,4,3,3,3,2,2) has multiplicities (2,3,1,2), which appear with multiplicities (1,2,1), which cover an initial interval but are not distinct, so p is not counted under a(27). The partition q = (5,5,5,4,4,4,3,3,2,2,1,1) has multiplicities (3,3,2,2,2), which appear with multiplicities (3,2), which are distinct but do not cover an initial interval, so q is not counted under a(39). The partition r = (3,3,2,1,1) has multiplicities (2,1,2), which appear with multiplicities (1,2), which are distinct and cover an initial interval, so r is counted under a(10).
Cf.
A098859,
A130091,
A317081,
A317090,
A320348,
A325329,
A325330,
A325337,
A325369,
A325370,
A325371.
-
normQ[m_]:=Or[m=={},Union[m]==Range[Max[m]]];
Table[Length[Select[IntegerPartitions[n],normQ[Length/@Split[Sort[Length/@Split[#]]]]&&UnsameQ@@Length/@Split[Sort[Length/@Split[#]]]&]],{n,0,30}]
A325371
Numbers whose prime signature has multiplicities of its parts all distinct and covering an initial interval of positive integers.
Original entry on oeis.org
1, 2, 3, 4, 5, 7, 8, 9, 11, 13, 16, 17, 19, 23, 25, 27, 29, 31, 32, 37, 41, 43, 47, 49, 53, 59, 60, 61, 64, 67, 71, 73, 79, 81, 83, 84, 89, 90, 97, 101, 103, 107, 109, 113, 120, 121, 125, 126, 127, 128, 131, 132, 137, 139, 140, 149, 150, 151, 156, 157, 163
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}
11: {5}
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}
37: {12}
Cf.
A055932,
A056239,
A098859,
A112798,
A118914,
A130091,
A317090,
A325329,
A325330,
A325331,
A325337,
A325369,
A325370.
A325373
Composite totally abnormal numbers. Heinz numbers of non-singleton totally abnormal integer partitions.
Original entry on oeis.org
9, 25, 27, 49, 81, 100, 121, 125, 169, 196, 225, 243, 289, 343, 361, 441, 484, 529, 625, 676, 729, 841, 961, 1000, 1089, 1156, 1225, 1331, 1369, 1444, 1521, 1681, 1764, 1849, 2116, 2187, 2197, 2209, 2401, 2601, 2744, 2809, 3025, 3125, 3249, 3364, 3375, 3481
Offset: 1
The sequence of terms together with their prime indices begins:
9: {2,2}
25: {3,3}
27: {2,2,2}
49: {4,4}
81: {2,2,2,2}
100: {1,1,3,3}
121: {5,5}
125: {3,3,3}
169: {6,6}
196: {1,1,4,4}
225: {2,2,3,3}
243: {2,2,2,2,2}
289: {7,7}
343: {4,4,4}
361: {8,8}
441: {2,2,4,4}
484: {1,1,5,5}
529: {9,9}
625: {3,3,3,3}
676: {1,1,6,6}
Cf.
A001597,
A055932,
A056239,
A112798,
A181819,
A317089,
A317090,
A317246,
A319152,
A319810,
A325332,
A325370,
A325372.
-
normQ[n_Integer]:=Or[n==1,PrimePi/@First/@FactorInteger[n]==Range[PrimeNu[n]]];
totabnQ[n_]:=And[!normQ[n],PrimeQ[n]||totabnQ[Times@@Prime/@Last/@If[n==1,{},FactorInteger[n]]]];
Select[Range[10000],!PrimeQ[#]&&totabnQ[#]&]
Showing 1-7 of 7 results.
Comments