A109297
Primal codes of finite permutations on positive integers.
Original entry on oeis.org
1, 2, 9, 12, 18, 40, 112, 125, 250, 352, 360, 540, 600, 675, 832, 1008, 1125, 1350, 1500, 2176, 2250, 2268, 2352, 2401, 3168, 3969, 4802, 4864, 7488, 7938, 10692, 11616, 11776, 14000, 19584, 21609, 27440, 28812, 29403, 29696, 32448, 35000, 37908, 43218, 43776
Offset: 1
Writing (prime(i))^j as i:j, we have the following table:
Primal Codes of Finite Permutations on Positive Integers
` ` ` 1 = { }
` ` ` 2 = 1:1
` ` ` 9 = 2:2
` ` `12 = 1:2 2:1
` ` `18 = 1:1 2:2
` ` `40 = 1:3 3:1
` ` 112 = 1:4 4:1
` ` 125 = 3:3
` ` 250 = 1:1 3:3
` ` 352 = 1:5 5:1
` ` 360 = 1:3 2:2 3:1
` ` 540 = 1:2 2:3 3:1
` ` 600 = 1:3 2:1 3:2
` ` 675 = 2:3 3:2
` ` 832 = 1:6 6:1
` `1008 = 1:4 2:2 4:1
` `1125 = 2:2 3:3
` `1350 = 1:1 2:3 3:2
` `1500 = 1:2 2:1 3:3
` `2176 = 1:7 7:1
` `2250 = 1:1 2:2 3:3
-
a:= proc(n) option remember; local k; for k from 1+`if`(n=1, 0,
a(n-1)) while (l-> sort(map(i-> i[2], l)) <> sort(map(
i-> numtheory[pi](i[1]), l)))(ifactors(k)[2]) do od; k
end:
seq(a(n), n=1..45); # Alois P. Heinz, Mar 08 2019
-
Select[Range[1000],#==1||Union[PrimePi/@First/@FactorInteger[#]]==Union[Last/@FactorInteger[#]]&] (* Gus Wiseman, Apr 02 2019 *)
-
is(n) = {my(f = factor(n), p = f[,1], e = vecsort(f[,2])); for(i=1, #p, if(primepi(p[i]) != e[i], return(0))); 1}; \\ Amiram Eldar, Jul 30 2022
A114639
Number of partitions of n such that the set of parts and the set of multiplicities of parts are disjoint.
Original entry on oeis.org
1, 0, 2, 2, 2, 3, 5, 4, 7, 7, 13, 16, 19, 23, 33, 34, 44, 58, 63, 80, 101, 112, 139, 171, 196, 234, 288, 328, 394, 478, 545, 658, 777, 881, 1050, 1236, 1414, 1666, 1936, 2216, 2592, 3018, 3428, 3992, 4604, 5243, 6069, 6986, 7951, 9139, 10447, 11892, 13625
Offset: 0
From _Gus Wiseman_, Apr 02 2019: (Start)
The a(2) = 2 through a(9) = 7 partitions:
(2) (3) (4) (5) (6) (7) (8) (9)
(11) (111) (1111) (32) (33) (43) (44) (54)
(11111) (42) (52) (53) (63)
(222) (1111111) (62) (72)
(111111) (2222) (432)
(3311) (222111)
(11111111) (111111111)
(End)
-
b:= proc(n, i, p, m) option remember; `if`(n=0, 1,
`if`(i<1, 0, b(n, i-1, p, select(x-> x x<=n-i*j, p union {i}),
select(x-> x b(n$2, {}$2):
seq(a(n), n=0..40); # Alois P. Heinz, Aug 09 2016
-
b[n_, i_, p_, m_] := b[n, i, p, m] = If[n == 0, 1, If[i<1, 0, b[n, i-1, p, Select[m, #Jean-François Alcover, Feb 05 2017, after Alois P. Heinz *)
Table[Length[Select[IntegerPartitions[n],Intersection[#,Length/@Split[#]]=={}&]],{n,0,30}] (* Gus Wiseman, Apr 02 2019 *)
A325705
Number of integer partitions of n containing all of their distinct multiplicities.
Original entry on oeis.org
1, 1, 0, 1, 3, 2, 4, 3, 7, 8, 16, 15, 24, 28, 39, 44, 68, 80, 98, 130, 167, 200, 259, 320, 396, 497, 601, 737, 910, 1107, 1335, 1631, 1983, 2372, 2887, 3439, 4166, 4949, 5940, 7043, 8450, 9980, 11884, 13984, 16679, 19493, 23162, 27050, 31937, 37334, 43926
Offset: 0
The partition (4,2,1,1,1,1) has distinct multiplicities {1,4}, both of which belong to the partition, so it is counted under a(10).
The a(0) = 1 through a(10) = 16 partitions:
() (1) (21) (22) (41) (51) (61) (71) (81) (91)
(31) (221) (321) (421) (431) (333) (541)
(211) (2211) (3211) (521) (531) (631)
(3111) (3221) (621) (721)
(4211) (3321) (3322)
(32111) (4221) (3331)
(41111) (5211) (4321)
(32211) (5221)
(6211)
(32221)
(33211)
(42211)
(43111)
(322111)
(421111)
(511111)
Cf.
A109297,
A114639,
A114640,
A181819,
A225486,
A290689,
A324753,
A324843,
A325702,
A325706,
A325707,
A325755.
-
Table[Length[Select[IntegerPartitions[n],SubsetQ[Sort[#],Sort[Length/@Split[#]]]&]],{n,0,30}]
A353391
Number of compositions of n that are empty, a singleton, or whose run-lengths are a subsequence that is already counted.
Original entry on oeis.org
1, 1, 1, 1, 2, 1, 3, 1, 1, 4, 5, 7, 9, 11, 15, 22, 38, 45, 87, 93
Offset: 0
The a(9) = 4 through a(14) = 15 compositions (A..E = 10..14):
(9) (A) (B) (C) (D) (E)
(333) (2233) (141122) (2244) (161122) (2255)
(121122) (3322) (221123) (4422) (221125) (5522)
(221121) (131122) (221132) (151122) (221134) (171122)
(221131) (221141) (221124) (221143) (221126)
(231122) (221142) (221152) (221135)
(321122) (221151) (221161) (221153)
(241122) (251122) (221162)
(421122) (341122) (221171)
(431122) (261122)
(521122) (351122)
(531122)
(621122)
(122121122)
(221121221)
The non-recursive reverse version is
A353403.
The consecutive version is
A353430.
These compositions are ranked by
A353431.
A114901 counts compositions with no runs of length 1.
A325705 counts partitions containing all of their distinct multiplicities.
A329739 counts compositions with all distinct run-length.
Cf.
A005811,
A032020,
A103295,
A114640,
A165413,
A181591,
A242882,
A324572,
A325702,
A333755,
A351013,
A353401.
-
yosQ[y_]:=Length[y]<=1||MemberQ[Subsets[y],Length/@Split[y]]&&yosQ[Length/@Split[y]];
Table[Length[Select[Join@@Permutations/@IntegerPartitions[n],yosQ]],{n,0,15}]
A353402
Numbers k such that the k-th composition in standard order has its own run-lengths as a subsequence (not necessarily consecutive).
Original entry on oeis.org
0, 1, 10, 21, 26, 43, 53, 58, 107, 117, 174, 186, 292, 314, 346, 348, 349, 373, 430, 442, 570, 585, 586, 629, 676, 693, 696, 697, 698, 699, 804, 826, 858, 860, 861, 885, 954, 1082, 1141, 1173, 1210, 1338, 1353, 1387, 1392, 1393, 1394, 1396, 1397, 1398, 1466
Offset: 0
The initial terms, their binary expansions, and the corresponding standard compositions:
0: 0 ()
1: 1 (1)
10: 1010 (2,2)
21: 10101 (2,2,1)
26: 11010 (1,2,2)
43: 101011 (2,2,1,1)
53: 110101 (1,2,2,1)
58: 111010 (1,1,2,2)
107: 1101011 (1,2,2,1,1)
117: 1110101 (1,1,2,2,1)
174: 10101110 (2,2,1,1,2)
186: 10111010 (2,1,1,2,2)
292: 100100100 (3,3,3)
314: 100111010 (3,1,1,2,2)
346: 101011010 (2,2,1,2,2)
348: 101011100 (2,2,1,1,3)
349: 101011101 (2,2,1,1,2,1)
373: 101110101 (2,1,1,2,2,1)
430: 110101110 (1,2,2,1,1,2)
442: 110111010 (1,2,1,1,2,2)
These compositions are counted by
A353390.
A005811 counts runs in binary expansion.
A333769 lists run-lengths of compositions in standard order.
Statistics of standard compositions:
Classes of standard compositions:
Cf.
A114640,
A165413,
A181819,
A318928,
A325705,
A329738,
A333224/
A333257,
A333755,
A353393,
A353403,
A353430.
-
stc[n_]:=Differences[Prepend[Join@@Position[ Reverse[IntegerDigits[n,2]],1],0]]//Reverse;
rosQ[y_]:=Length[y]==0||MemberQ[Subsets[y],Length/@Split[y]];
Select[Range[0,100],rosQ[stc[#]]&]
A353403
Number of compositions of n whose own reversed run-lengths are a subsequence (not necessarily consecutive).
Original entry on oeis.org
1, 1, 0, 0, 3, 2, 5, 12, 16, 30, 45, 94, 159, 285, 477, 864, 1487, 2643
Offset: 0
The a(0) = 1 through a(7) = 12 compositions:
() (1) . . (22) (1121) (1113) (1123)
(112) (1211) (1122) (1132)
(211) (1221) (2311)
(2211) (3211)
(3111) (11131)
(11212)
(11221)
(12112)
(12211)
(13111)
(21121)
(21211)
The non-reversed recursive consecutive version is
A353430.
A325705 counts partitions containing all of their distinct multiplicities.
A329739 counts compositions with all distinct run-lengths, for runs
A351013.
-
Table[Length[Select[Join@@Permutations/@ IntegerPartitions[n],MemberQ[Subsets[#],Reverse[Length/@Split[#]]]&]],{n,0,15}]
A353431
Numbers k such that the k-th composition in standard order is empty, a singleton, or has its own run-lengths as a subsequence (not necessarily consecutive) that is already counted.
Original entry on oeis.org
0, 1, 2, 4, 8, 10, 16, 32, 43, 58, 64, 128, 256, 292, 349, 442, 512, 586, 676, 697, 826, 1024, 1210, 1338, 1393, 1394, 1396, 1594, 2048, 2186, 2234, 2618, 2696, 2785, 2786, 2792, 3130, 4096, 4282, 4410, 4666, 5178, 5569, 5570, 5572, 5576, 5584, 6202, 8192
Offset: 1
The initial terms, their binary expansions, and the corresponding standard compositions:
0: 0 ()
1: 1 (1)
2: 10 (2)
4: 100 (3)
8: 1000 (4)
10: 1010 (2,2)
16: 10000 (5)
32: 100000 (6)
43: 101011 (2,2,1,1)
58: 111010 (1,1,2,2)
64: 1000000 (7)
128: 10000000 (8)
256: 100000000 (9)
292: 100100100 (3,3,3)
349: 101011101 (2,2,1,1,2,1)
442: 110111010 (1,2,1,1,2,2)
512: 1000000000 (10)
586: 1001001010 (3,3,2,2)
676: 1010100100 (2,2,3,3)
697: 1010111001 (2,2,1,1,3,1)
The non-recursive version for partitions is
A325755, counted by
A325702.
These compositions are counted by
A353391.
A005811 counts runs in binary expansion.
Statistics of standard compositions:
Classes of standard compositions:
Cf.
A032020,
A044813,
A114640,
A165413,
A181819,
A329739,
A318928,
A325705,
A333224,
A353427,
A353403.
-
stc[n_]:=Differences[Prepend[Join@@ Position[Reverse[IntegerDigits[n,2]],1],0]]//Reverse;
rorQ[y_]:=Length[y]<=1||MemberQ[Subsets[y],Length/@Split[y]]&& rorQ[Length/@Split[y]];
Select[Range[0,100],rorQ[stc[#]]&]
A352142
Numbers whose prime factorization has all odd indices and all odd exponents.
Original entry on oeis.org
1, 2, 5, 8, 10, 11, 17, 22, 23, 31, 32, 34, 40, 41, 46, 47, 55, 59, 62, 67, 73, 82, 83, 85, 88, 94, 97, 103, 109, 110, 115, 118, 125, 127, 128, 134, 136, 137, 146, 149, 155, 157, 160, 166, 167, 170, 179, 184, 187, 191, 194, 197, 205, 206, 211, 218, 227, 230
Offset: 1
The terms together with their prime indices begin:
1 = 1
2 = prime(1)
5 = prime(3)
8 = prime(1)^3
10 = prime(1) prime(3)
11 = prime(5)
17 = prime(7)
22 = prime(1) prime(5)
23 = prime(9)
31 = prime(11)
32 = prime(1)^5
34 = prime(1) prime(7)
40 = prime(1)^3 prime(3)
The restriction to primes is
A031368.
These partitions are counted by
A117958.
A352140 = even indices with odd exponents, counted by
A055922 aerated.
A352143 = odd indices with odd conjugate indices, counted by
A053253 aerated.
Cf.
A000720,
A028260,
A055396,
A061395,
A106529,
A181819,
A195017,
A241638,
A276078,
A324517,
A324524,
A324525,
A325698,
A325700.
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Select[Range[100],#==1||And@@OddQ/@PrimePi/@First/@FactorInteger[#]&&And@@OddQ/@Last/@FactorInteger[#]&]
-
from itertools import count, islice
from sympy import primepi, factorint
def A352142_gen(startvalue=1): # generator of terms >= startvalue
return filter(lambda k:all(map(lambda x:x[1]%2 and primepi(x[0])%2, factorint(k).items())),count(max(startvalue,1)))
A352142_list = list(islice(A352142_gen(),30)) # Chai Wah Wu, Mar 18 2022
A353430
Number of integer compositions of n that are empty, a singleton, or whose own run-lengths are a consecutive subsequence that is already counted.
Original entry on oeis.org
1, 1, 1, 1, 2, 1, 3, 1, 1, 4, 5, 7, 9, 11, 15, 16, 22, 25, 37, 37, 45
Offset: 0
The a(n) compositions for selected n (A..E = 10..14):
n=4: n=6: n=9: n=10: n=12: n=14:
-----------------------------------------------------------
(4) (6) (9) (A) (C) (E)
(22) (1122) (333) (2233) (2244) (2255)
(2211) (121122) (3322) (4422) (5522)
(221121) (131122) (151122) (171122)
(221131) (221124) (221126)
(221142) (221135)
(221151) (221153)
(241122) (221162)
(421122) (221171)
(261122)
(351122)
(531122)
(621122)
(122121122)
(221121221)
A114901 counts compositions with no runs of length 1.
A329739 counts compositions with all distinct run-lengths.
Cf.
A005811,
A032020,
A103295,
A114640,
A165413,
A242882,
A325705,
A333755,
A351013,
A353400,
A353401.
-
yoyQ[y_]:=Length[y]<=1||MemberQ[Join@@Table[Take[y,{i,j}],{i,Length[y]},{j,i,Length[y]}],Length/@Split[y]]&&yoyQ[Length/@Split[y]];
Table[Length[Select[Join@@Permutations/@IntegerPartitions[n],yoyQ]],{n,0,15}]
A325706
Heinz numbers of integer partitions containing all of their distinct multiplicities.
Original entry on oeis.org
1, 2, 6, 9, 10, 12, 14, 18, 22, 26, 30, 34, 36, 38, 40, 42, 46, 58, 60, 62, 66, 70, 74, 78, 82, 84, 86, 90, 94, 102, 106, 110, 112, 114, 118, 120, 122, 125, 126, 130, 132, 134, 138, 142, 146, 150, 154, 156, 158, 166, 170, 174, 178, 180, 182, 186, 190, 194, 198
Offset: 1
The sequence of terms together with their prime indices begins:
1: {}
2: {1}
6: {1,2}
9: {2,2}
10: {1,3}
12: {1,1,2}
14: {1,4}
18: {1,2,2}
22: {1,5}
26: {1,6}
30: {1,2,3}
34: {1,7}
36: {1,1,2,2}
38: {1,8}
40: {1,1,1,3}
42: {1,2,4}
46: {1,9}
58: {1,10}
60: {1,1,2,3}
62: {1,11}
Cf.
A056239,
A109297,
A112798,
A114639,
A114640,
A181819,
A225486,
A290689,
A324753,
A324843,
A325702,
A325705,
A325707,
A325755.
Showing 1-10 of 29 results.
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