A337452
Number of relatively prime strict integer partitions of n with no 1's.
Original entry on oeis.org
0, 0, 0, 0, 0, 1, 0, 2, 1, 3, 2, 6, 3, 9, 7, 11, 11, 20, 15, 28, 24, 35, 36, 55, 47, 73, 71, 95, 96, 136, 123, 180, 177, 226, 235, 305, 299, 403, 406, 503, 523, 668, 662, 852, 873, 1052, 1115, 1370, 1391, 1720, 1784, 2125, 2252, 2701, 2786, 3348, 3520, 4116
Offset: 0
The a(5) = 1 through a(16) = 11 partitions (A = 10, B = 11, C = 12, D = 13):
32 43 53 54 73 65 75 76 95 87 97
52 72 532 74 543 85 B3 B4 B5
432 83 732 94 653 D2 D3
92 A3 743 654 754
542 B2 752 753 763
632 643 932 762 853
652 5432 843 943
742 852 952
832 942 B32
A32 6532
6432 7432
A078374 is the version allowing 1's.
A332004 is the ordered version allowing 1's.
A337450 is the ordered non-strict version.
A337485 is the pairwise coprime version.
A000837 counts relatively prime partitions.
A078374 counts relatively prime strict partitions.
A002865 counts partitions with no 1's.
A212804 counts compositions with no 1's.
A291166 appears to rank relatively prime compositions.
A337561 counts pairwise coprime strict compositions.
-
Table[Length[Select[IntegerPartitions[n],UnsameQ@@#&&!MemberQ[#,1]&&GCD@@#==1&]],{n,0,15}]
A366842
Number of integer partitions of n whose odd parts have a common divisor > 1.
Original entry on oeis.org
0, 0, 0, 1, 0, 2, 1, 4, 1, 8, 3, 13, 6, 21, 10, 36, 15, 53, 28, 80, 41, 122, 63, 174, 97, 250, 140, 359, 201, 496, 299, 685, 410, 949, 575, 1284, 804, 1726, 1093, 2327, 1482, 3076, 2023, 4060, 2684, 5358, 3572, 6970, 4745, 9050, 6221, 11734, 8115, 15060, 10609
Offset: 0
The a(3) = 1 through a(11) = 13 partitions:
(3) . (5) (3,3) (7) (3,3,2) (9) (5,5) (11)
(3,2) (4,3) (5,4) (4,3,3) (6,5)
(5,2) (6,3) (3,3,2,2) (7,4)
(3,2,2) (7,2) (8,3)
(3,3,3) (9,2)
(4,3,2) (4,4,3)
(5,2,2) (5,4,2)
(3,2,2,2) (6,3,2)
(7,2,2)
(3,3,3,2)
(4,3,2,2)
(5,2,2,2)
(3,2,2,2,2)
A000740 counts relatively prime compositions.
A239261 counts partitions with (sum of odd parts) = (sum of even parts).
Cf.
A007359,
A051424,
A055922,
A066208,
A078374,
A087436,
A116598,
A337485,
A366843,
A366844,
A366845.
-
Table[Length[Select[IntegerPartitions[n], GCD@@Select[#,OddQ]>1&]], {n,0,30}]
-
from math import gcd
from sympy.utilities.iterables import partitions
def A366842(n): return sum(1 for p in partitions(n) if gcd(*(q for q in p if q&1))>1) # Chai Wah Wu, Oct 28 2023
A366843
Number of integer partitions of n into odd, relatively prime parts.
Original entry on oeis.org
1, 1, 1, 1, 2, 2, 3, 4, 6, 6, 9, 11, 13, 17, 21, 23, 32, 37, 42, 53, 62, 70, 88, 103, 116, 139, 164, 184, 220, 255, 283, 339, 390, 435, 511, 578, 653, 759, 863, 963, 1107, 1259, 1401, 1609, 1814, 2015, 2303, 2589, 2878, 3259, 3648, 4058, 4580, 5119, 5672, 6364
Offset: 0
The a(1) = 1 through a(8) = 6 partitions:
(1) (11) (111) (31) (311) (51) (331) (53)
(1111) (11111) (3111) (511) (71)
(111111) (31111) (3311)
(1111111) (5111)
(311111)
(11111111)
A000740 counts relatively prime compositions.
A366842 counts partitions whose odd parts have a common divisor > 1.
Cf.
A007359,
A047967,
A055922,
A066208,
A113685,
A116598,
A289509,
A289508,
A302697,
A337485,
A366845,
A366848,
A366849.
-
Table[Length[Select[IntegerPartitions[n],#=={}||And@@OddQ/@#&&GCD@@#==1&]],{n,0,30}]
-
from math import gcd
from sympy.utilities.iterables import partitions
def A366843(n): return sum(1 for p in partitions(n) if all(d&1 for d in p) and gcd(*p)==1) # Chai Wah Wu, Oct 30 2023
A337450
Number of relatively prime compositions of n with no 1's.
Original entry on oeis.org
0, 0, 0, 0, 0, 2, 0, 7, 5, 17, 17, 54, 51, 143, 168, 358, 482, 986, 1313, 2583, 3663, 6698, 9921, 17710, 26489, 46352, 70928, 121137, 188220, 317810, 497322, 832039, 1313501, 2177282, 3459041, 5702808, 9094377, 14930351, 23895672, 39084070, 62721578
Offset: 0
The a(5) = 2 through a(10) = 17 compositions (empty column indicated by dot):
(2,3) . (2,5) (3,5) (2,7) (3,7)
(3,2) (3,4) (5,3) (4,5) (7,3)
(4,3) (2,3,3) (5,4) (2,3,5)
(5,2) (3,2,3) (7,2) (2,5,3)
(2,2,3) (3,3,2) (2,2,5) (3,2,5)
(2,3,2) (2,3,4) (3,3,4)
(3,2,2) (2,4,3) (3,4,3)
(2,5,2) (3,5,2)
(3,2,4) (4,3,3)
(3,4,2) (5,2,3)
(4,2,3) (5,3,2)
(4,3,2) (2,2,3,3)
(5,2,2) (2,3,2,3)
(2,2,2,3) (2,3,3,2)
(2,2,3,2) (3,2,2,3)
(2,3,2,2) (3,2,3,2)
(3,2,2,2) (3,3,2,2)
A000740 is the version allowing 1's.
2*
A055684(n) is the case of length 2.
A337452 is the unordered strict version.
A000837 counts relatively prime partitions.
A002865 counts partitions with no 1's.
A101268 counts singleton or pairwise coprime compositions.
A212804 counts compositions with no 1's.
A291166 appears to rank relatively prime compositions.
A337462 counts pairwise coprime compositions.
-
b:= proc(n, g) option remember; `if`(n=0,
`if`(g=1, 1, 0), add(b(n-j, igcd(g, j)), j=2..n))
end:
a:= n-> b(n, 0):
seq(a(n), n=0..42);
-
Table[Length[Select[Join@@Permutations/@IntegerPartitions[n],!MemberQ[#,1]&&GCD@@#==1&]],{n,0,15}]
A337451
Number of relatively prime strict compositions of n with no 1's.
Original entry on oeis.org
0, 0, 0, 0, 0, 2, 0, 4, 2, 10, 8, 20, 14, 34, 52, 72, 90, 146, 172, 244, 390, 502, 680, 956, 1218, 1686, 2104, 3436, 4078, 5786, 7200, 10108, 12626, 17346, 20876, 32836, 38686, 53674, 67144, 91528, 113426, 152810, 189124, 245884, 343350, 428494, 552548, 719156
Offset: 0
The a(5) = 2 through a(10) = 8 compositions (empty column indicated by dot):
(2,3) . (2,5) (3,5) (2,7) (3,7)
(3,2) (3,4) (5,3) (4,5) (7,3)
(4,3) (5,4) (2,3,5)
(5,2) (7,2) (2,5,3)
(2,3,4) (3,2,5)
(2,4,3) (3,5,2)
(3,2,4) (5,2,3)
(3,4,2) (5,3,2)
(4,2,3)
(4,3,2)
A032022 does not require relative primality.
A302698 is the unordered non-strict version.
A332004 is the version allowing 1's.
A000837 counts relatively prime partitions.
A032020 counts strict compositions.
A078374 counts strict relatively prime partitions.
A002865 counts partitions with no 1's.
A212804 counts compositions with no 1's.
A291166 appears to rank relatively prime compositions.
A337462 counts pairwise coprime compositions.
A337561 counts strict pairwise coprime compositions.
-
Table[Length[Select[Join@@Permutations/@IntegerPartitions[n],UnsameQ@@#&&!MemberQ[#,1]&&GCD@@#==1&]],{n,0,15}]
A337602
Number of ordered triples of positive integers summing to n whose set of distinct parts is pairwise coprime, where a singleton is always considered coprime.
Original entry on oeis.org
0, 0, 0, 1, 3, 6, 10, 9, 18, 16, 24, 21, 43, 24, 51, 31, 54, 42, 94, 45, 102, 55, 99, 69, 163, 66, 150, 88, 168, 96, 265, 93, 228, 121, 246, 126, 337, 132, 315, 169, 342, 162, 487, 165, 420, 217, 411, 213, 619, 207, 558, 259, 540, 258, 784, 264, 654, 325, 660
Offset: 0
The a(3) = 1 through a(8) = 18 triples:
(1,1,1) (1,1,2) (1,1,3) (1,1,4) (1,1,5) (1,1,6)
(1,2,1) (1,2,2) (1,2,3) (1,3,3) (1,2,5)
(2,1,1) (1,3,1) (1,3,2) (1,5,1) (1,3,4)
(2,1,2) (1,4,1) (2,2,3) (1,4,3)
(2,2,1) (2,1,3) (2,3,2) (1,5,2)
(3,1,1) (2,2,2) (3,1,3) (1,6,1)
(2,3,1) (3,2,2) (2,1,5)
(3,1,2) (3,3,1) (2,3,3)
(3,2,1) (5,1,1) (2,5,1)
(4,1,1) (3,1,4)
(3,2,3)
(3,3,2)
(3,4,1)
(4,1,3)
(4,3,1)
(5,1,2)
(5,2,1)
(6,1,1)
A337603 does not consider a singleton to be coprime unless it is (1).
A337664 counts these compositions of any length.
A000740 counts relatively prime compositions.
A337561 counts pairwise coprime strict compositions.
A000217 counts 3-part compositions.
A023023 counts relatively prime 3-part partitions.
A051424 counts pairwise coprime or singleton partitions.
A101268 counts pairwise coprime or singleton compositions.
A305713 counts pairwise coprime strict partitions.
A327516 counts pairwise coprime partitions.
A333227 ranks pairwise coprime compositions.
A333228 ranks compositions whose distinct parts are pairwise coprime.
A337461 counts pairwise coprime 3-part compositions.
Cf.
A000212,
A007359,
A087087,
A284825,
A302696,
A304709,
A304712,
A307719,
A328673,
A335235,
A335238,
A337483,
A337562,
A337601.
-
Table[Length[Select[Join@@Permutations/@IntegerPartitions[n,{3}],SameQ@@#||CoprimeQ@@Union[#]&]],{n,0,100}]
A101391
Triangle read by rows: T(n,k) is the number of compositions of n into k parts x_1, x_2, ..., x_k such that gcd(x_1,x_2,...,x_k) = 1 (1<=k<=n).
Original entry on oeis.org
1, 0, 1, 0, 2, 1, 0, 2, 3, 1, 0, 4, 6, 4, 1, 0, 2, 9, 10, 5, 1, 0, 6, 15, 20, 15, 6, 1, 0, 4, 18, 34, 35, 21, 7, 1, 0, 6, 27, 56, 70, 56, 28, 8, 1, 0, 4, 30, 80, 125, 126, 84, 36, 9, 1, 0, 10, 45, 120, 210, 252, 210, 120, 45, 10, 1, 0, 4, 42, 154, 325, 461, 462, 330, 165, 55, 11, 1, 0, 12, 66, 220, 495, 792, 924, 792, 495, 220, 66, 12, 1
Offset: 1
T(6,3)=9 because we have 411,141,114 and the six permutations of 123 (222 does not qualify).
T(8,3)=18 because binomial(0,2)*mobius(8/1)+binomial(1,2)*mobius(8/2)+binomial(3,2)*mobius(8/4)+binomial(7,2)*mobius(8/8)=0+0+(-3)+21=18.
Triangle begins:
1;
0, 1;
0, 2, 1;
0, 2, 3, 1;
0, 4, 6, 4, 1;
0, 2, 9, 10, 5, 1;
0, 6, 15, 20, 15, 6, 1;
0, 4, 18, 34, 35, 21, 7, 1;
0, 6, 27, 56, 70, 56, 28, 8, 1;
0, 4, 30, 80, 125, 126, 84, 36, 9, 1;
0, 10, 45, 120, 210, 252, 210, 120, 45, 10, 1;
0, 4, 42, 154, 325, 461, 462, 330, 165, 55, 11, 1;
0, 12, 66, 220, 495, 792, 924, 792, 495, 220, 66, 12, 1;
...
From _Gus Wiseman_, Oct 19 2020: (Start)
Row n = 6 counts the following compositions:
(15) (114) (1113) (11112) (111111)
(51) (123) (1122) (11121)
(132) (1131) (11211)
(141) (1212) (12111)
(213) (1221) (21111)
(231) (1311)
(312) (2112)
(321) (2121)
(411) (2211)
(3111)
Missing are: (42), (24), (33), (222).
(End)
- Alois P. Heinz, Rows n = 1..200, flattened
- H. W. Gould, Binomial coefficients, the bracket function and compositions with relatively prime summands, Fib. Quart. 2(4) (1964), 241-260.
- Temba Shonhiwa, Compositions with pairwise relatively prime summands within a restricted setting, Fibonacci Quart. 44 (2006), no. 4, 316-323.
A000837 counts relatively prime partitions.
A135278 counts compositions by length.
A282748 is the pairwise coprime instead of relatively prime version.
A291166 ranks these compositions (evidently).
-
with(numtheory): T:=proc(n,k) local d, j, b: d:=divisors(n): for j from 1 to tau(n) do b[j]:=binomial(d[j]-1,k-1)*mobius(n/d[j]) od: sum(b[i],i=1..tau(n)) end: for n from 1 to 14 do seq(T(n,k),k=1..n) od; # yields the sequence in triangular form
# second Maple program:
b:= proc(n, g) option remember; `if`(n=0, `if`(g=1, 1, 0),
expand(add(b(n-j, igcd(g, j))*x, j=1..n)))
end:
T:= (n, k)-> coeff(b(n,0),x,k):
seq(seq(T(n,k), k=1..n), n=1..14); # Alois P. Heinz, May 05 2025
-
t[n_, k_] := Sum[Binomial[d-1, k-1]*MoebiusMu[n/d], {d, Divisors[n]}]; Table[t[n, k], {n, 2, 14}, {k, 2, n}] // Flatten (* Jean-François Alcover, Jan 20 2014 *)
Table[Length[Select[Join@@Permutations/@IntegerPartitions[n,{k}],GCD@@#==1&]],{n,10},{k,2,n}] (* change {k,2,n} to {k,1,n} for the version with zeros. - Gus Wiseman, Oct 19 2020 *)
-
T(n, k) = sumdiv(n, d, binomial(d-1, k-1)*moebius(n/d)); \\ Michel Marcus, Mar 09 2016
A337600
Number of unordered triples of positive integers summing to n whose set of distinct parts is pairwise coprime, where a singleton is always considered coprime.
Original entry on oeis.org
0, 0, 0, 1, 1, 2, 3, 3, 4, 5, 5, 6, 9, 7, 10, 8, 11, 11, 18, 12, 19, 13, 19, 17, 30, 16, 28, 20, 31, 23, 47, 23, 42, 26, 45, 27, 60, 31, 57, 35, 61, 37, 85, 38, 75, 43, 74, 47, 108, 45, 98, 52, 96, 56, 136, 54, 115, 64, 117, 67, 175, 65, 139, 76, 144, 75, 195
Offset: 0
The a(3) = 1 through a(14) = 10 partitions (A = 10, B = 11, C = 12):
111 211 221 222 322 332 333 433 443 444 544 554
311 321 331 431 441 532 533 543 553 743
411 511 521 522 541 551 552 661 752
611 531 721 722 651 733 761
711 811 731 732 751 833
911 741 922 851
831 B11 941
921 A31
A11 B21
C11
A304712 counts these partitions of any length.
A307719 is the strict case except for any number of 1's.
A337601 does not consider a singleton to be coprime unless it is (1).
A337664 counts compositions of this type and any length.
A000217 counts 3-part compositions.
A000837 counts relatively prime partitions.
A023023 counts relatively prime 3-part partitions.
A051424 counts pairwise coprime or singleton partitions.
A101268 counts pairwise coprime or singleton compositions.
A304709 counts partitions whose distinct parts are pairwise coprime.
A305713 counts pairwise coprime strict partitions.
A327516 counts pairwise coprime partitions.
A333227 ranks pairwise coprime compositions.
A333228 ranks compositions whose distinct parts are pairwise coprime.
A337461 counts pairwise coprime length-3 compositions.
A337563 counts pairwise coprime length-3 partitions with no 1's.
Cf.
A001840,
A007359,
A007360,
A014612,
A087087,
A284825,
A302569,
A302696,
A328673,
A335235,
A337603,
A337695.
-
Table[Length[Select[IntegerPartitions[n,{3}],SameQ@@#||CoprimeQ@@Union[#]&]],{n,0,100}]
A337664
Number of compositions of n whose set of distinct parts is pairwise coprime, where a singleton is always considered coprime.
Original entry on oeis.org
1, 1, 2, 4, 8, 16, 30, 58, 111, 210, 396, 750, 1420, 2688, 5079, 9586, 18092, 34157, 64516, 121899, 230373, 435463, 823379, 1557421, 2946938, 5578111, 10561990, 20005129, 37902514, 71832373, 136173273, 258211603, 489738627, 929074448, 1762899110, 3345713034
Offset: 0
The a(0) = 1 through a(5) = 16 compositions:
() (1) (2) (3) (4) (5)
(11) (12) (13) (14)
(21) (22) (23)
(111) (31) (32)
(112) (41)
(121) (113)
(211) (122)
(1111) (131)
(212)
(221)
(311)
(1112)
(1121)
(1211)
(2111)
(11111)
A337665 does not consider a singleton to be coprime unless it is (1).
A337695 ranks the complement of these compositions.
A000740 counts relatively prime compositions.
A051424 counts pairwise coprime or singleton partitions.
A101268 counts pairwise coprime or singleton compositions.
A305713 counts pairwise coprime strict partitions.
A327516 counts pairwise coprime partitions.
A333227 ranks pairwise coprime compositions.
A333228 ranks compositions whose distinct parts are pairwise coprime.
A337461 counts pairwise coprime length-3 compositions.
A337561 counts pairwise coprime strict compositions.
Cf.
A007359,
A007360,
A087087,
A302569,
A304709,
A307719,
A335235,
A335238,
A335239,
A337562,
A337603,
A337667.
-
Table[Length[Select[Join@@Permutations/@IntegerPartitions[n],SameQ@@#||CoprimeQ@@Union[#]&]],{n,0,15}]
A366844
Number of strict integer partitions of n into odd relatively prime parts.
Original entry on oeis.org
0, 1, 0, 0, 1, 0, 1, 0, 2, 1, 2, 1, 2, 2, 3, 3, 5, 4, 4, 5, 6, 7, 8, 8, 9, 11, 12, 12, 15, 16, 15, 19, 23, 23, 26, 28, 30, 34, 37, 38, 44, 48, 48, 56, 62, 63, 72, 77, 82, 92, 96, 102, 116, 124, 128, 142, 155, 162, 178, 191, 200, 222, 236, 246, 276, 291, 303, 334
Offset: 0
The a(n) partitions for n = 1, 8, 14, 17, 16, 20, 21:
(1) (5,3) (9,5) (9,5,3) (9,7) (11,9) (9,7,5)
(7,1) (11,3) (9,7,1) (11,5) (13,7) (11,7,3)
(13,1) (11,5,1) (13,3) (17,3) (11,9,1)
(13,3,1) (15,1) (19,1) (13,5,3)
(7,5,3,1) (9,7,3,1) (13,7,1)
(11,5,3,1) (15,5,1)
(17,3,1)
This is the relatively prime case of
A000700.
The pairwise coprime version is the odd-part case of
A007360.
The halved even version is
A078374 aerated.
The complement is counted by the strict case of
A366852, with evens
A018783.
A113685 counts partitions by sum of odd parts, rank statistic
A366528.
A366842 counts partitions whose odd parts have a common divisor > 1.
Cf.
A007359,
A047967,
A055922,
A066208,
A116598,
A239261,
A302697,
A337485,
A365067,
A366845,
A366848.
-
Table[Length[Select[IntegerPartitions[n], And@@OddQ/@#&&UnsameQ@@#&&GCD@@#==1&]],{n,0,30}]
-
from math import gcd
from sympy.utilities.iterables import partitions
def A366844(n): return sum(1 for p in partitions(n) if all(d==1 for d in p.values()) and all(d&1 for d in p) and gcd(*p)==1) # Chai Wah Wu, Oct 30 2023
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