A384175
Number of subsets of {1..n} with all distinct lengths of maximal runs (increasing by 1).
Original entry on oeis.org
1, 2, 4, 7, 13, 24, 44, 77, 135, 236, 412, 713, 1215, 2048, 3434, 5739, 9559, 15850, 26086, 42605, 69133, 111634, 179602, 288069, 460553, 733370, 1162356, 1833371, 2878621, 4501856, 7016844, 10905449, 16904399, 26132460, 40279108, 61885621, 94766071, 144637928
Offset: 0
The subset {2,3,5,6,7,9} has maximal runs ((2,3),(5,6,7),(9)), with lengths (2,3,1), so is counted under a(9).
The a(0) = 1 through a(4) = 13 subsets:
{} {} {} {} {}
{1} {1} {1} {1}
{2} {2} {2}
{1,2} {3} {3}
{1,2} {4}
{2,3} {1,2}
{1,2,3} {2,3}
{3,4}
{1,2,3}
{1,2,4}
{1,3,4}
{2,3,4}
{1,2,3,4}
For equal instead of distinct lengths we have
A243815.
These subsets are ranked by
A328592.
The complement is counted by
A384176.
For permutations instead of subsets we have
A384891, equal instead of distinct
A384892.
A034839 counts subsets by number of maximal runs, for strict partitions
A116674.
A098859 counts Wilf partitions (distinct multiplicities), complement
A336866.
Cf.
A000009,
A010027,
A044813,
A047993,
A242882,
A325325,
A329739,
A351202,
A383013,
A384889,
A384890.
-
Table[Length[Select[Subsets[Range[n]],UnsameQ@@Length/@Split[#,#2==#1+1&]&]],{n,0,10}]
-
lista(n)={my(o=(1-x^(n+1))/(1-x)*O(y^(n+2)),p=prod(i=1,n,1+o+x*y^(i+1)/(1-y),1/(1-y)));p=subst(serlaplace(p),x,1);Vec(p-1)} \\ Christian Sievers, Jun 18 2025
A384177
Number of subsets of {1..n} with all distinct lengths of maximal anti-runs (increasing by more than 1).
Original entry on oeis.org
1, 2, 3, 5, 10, 19, 35, 62, 109, 197, 364, 677, 1251, 2288, 4143, 7443, 13318, 23837, 42809, 77216, 139751, 253293, 458800, 829237, 1494169, 2683316, 4804083, 8580293, 15301324, 27270061, 48607667, 86696300, 154758265, 276453311, 494050894, 882923051
Offset: 0
The subset {1,2,4,5,7,10} has maximal anti-runs ((1),(2,4),(5,7,10)), with lengths (1,2,3), so is counted under a(10).
The a(0) = 1 through a(5) = 19 subsets:
{} {} {} {} {} {}
{1} {1} {1} {1} {1}
{2} {2} {2} {2}
{3} {3} {3}
{1,3} {4} {4}
{1,3} {5}
{1,4} {1,3}
{2,4} {1,4}
{1,2,4} {1,5}
{1,3,4} {2,4}
{2,5}
{3,5}
{1,2,4}
{1,2,5}
{1,3,4}
{1,3,5}
{1,4,5}
{2,3,5}
{2,4,5}
These subsets are ranked by
A384879.
For equal instead of distinct lengths we have
A384889, for runs
A243815.
A034839 counts subsets by number of maximal runs, for strict partitions
A116674.
A098859 counts Wilf partitions (distinct multiplicities), complement
A336866.
Cf.
A000009,
A010027,
A044813,
A047993,
A106529,
A123513,
A242882,
A325325,
A328592,
A329739,
A351202,
A384890.
-
Table[Length[Select[Subsets[Range[n]],UnsameQ@@Length/@Split[#,#2!=#1+1&]&]],{n,0,10}]
-
lista(n)={my(o=(1-x^(n+1))/(1-x)*O(y*y^n),p=prod(i=1,(n+1)\2,1+o+x*y^(2*i-1)/(1-y)^(i-1)));p=subst(serlaplace(p),x,1);Vec((p-y)/(1-y)^2)} \\ Christian Sievers, Jun 18 2025
A384176
Number of subsets of {1..n} without all distinct lengths of maximal runs (increasing by 1).
Original entry on oeis.org
0, 0, 0, 1, 3, 8, 20, 51, 121, 276, 612, 1335, 2881, 6144, 12950, 27029, 55977, 115222, 236058, 481683, 979443
Offset: 0
The subset {1,3,4,8,9} has maximal runs ((1),(3,4),(8,9)), with lengths (1,2,2), so is counted under a(10).
The a(0) = 0 through a(6) = 20 subsets:
. . . {1,3} {1,3} {1,3} {1,3}
{1,4} {1,4} {1,4}
{2,4} {1,5} {1,5}
{2,4} {1,6}
{2,5} {2,4}
{3,5} {2,5}
{1,3,5} {2,6}
{1,2,4,5} {3,5}
{3,6}
{4,6}
{1,3,5}
{1,3,6}
{1,4,6}
{2,4,6}
{1,2,4,5}
{1,2,4,6}
{1,2,5,6}
{1,3,4,6}
{1,3,5,6}
{2,3,5,6}
For equal instead of distinct lengths the complement is
A243815.
These subsets are ranked by the non-members of
A328592.
The complement is counted by
A384175.
A034839 counts subsets by number of maximal runs, for strict partitions
A116674.
A098859 counts Wilf partitions (distinct multiplicities), complement
A336866.
-
Table[Length[Select[Subsets[Range[n]],!UnsameQ@@Length/@Split[#,#2==#1+1&]&]],{n,0,10}]
A384886
Number of strict integer partitions of n with all equal lengths of maximal runs (decreasing by 1).
Original entry on oeis.org
1, 1, 1, 2, 2, 3, 4, 4, 4, 7, 7, 8, 11, 11, 14, 17, 19, 20, 27, 27, 35, 38, 45, 47, 60, 63, 75, 84, 97, 104, 127, 134, 155, 175, 196, 218, 251, 272, 307, 346, 384, 424, 480, 526, 586, 658, 719, 798, 890, 979, 1078, 1201, 1315, 1451, 1603, 1762, 1934, 2137
Offset: 0
The strict partition y = (7,6,5,3,2,1) has maximal runs ((7,6,5),(3,2,1)), with lengths (3,3), so y is counted under a(24).
The a(1) = 1 through a(14) = 14 partitions (A-E = 10-14):
1 2 3 4 5 6 7 8 9 A B C D E
21 31 32 42 43 53 54 64 65 75 76 86
41 51 52 62 63 73 74 84 85 95
321 61 71 72 82 83 93 94 A4
81 91 92 A2 A3 B3
432 631 A1 B1 B2 C2
531 4321 641 543 C1 D1
731 642 742 752
741 751 842
831 841 851
5421 931 941
A31
5432
6521
For subsets instead of strict partitions we have
A243815, distinct lengths
A384175.
For distinct instead of equal lengths we have
A384178, for anti-runs
A384880.
Cf.
A000217,
A008284,
A044813,
A047966,
A089259,
A325324,
A325325,
A329739,
A382857,
A383013,
A383708,
A384176.
-
Table[Length[Select[IntegerPartitions[n],UnsameQ@@#&&SameQ@@Length/@Split[#,#2==#1-1&]&]],{n,0,15}]
-
A_q(N) = {Vec(1+sum(k=1,floor(-1/2+sqrt(2+2*N)), sum(i=1,(N/(k*(k+1)/2))+1, q^(k*(k+1)*i^2/2)/prod(j=1,i, 1 - q^(j*k)))) + O('q^(N+1)))} \\ John Tyler Rascoe, Aug 21 2025
A243815
Number of length n words on alphabet {0,1} such that the length of every maximal block of 0's (runs) is the same.
Original entry on oeis.org
1, 2, 4, 8, 14, 24, 39, 62, 97, 151, 233, 360, 557, 864, 1344, 2099, 3290, 5176, 8169, 12931, 20524, 32654, 52060, 83149, 133012, 213069, 341718, 548614, 881572, 1417722, 2281517, 3673830, 5918958, 9540577, 15384490, 24817031, 40045768, 64637963, 104358789
Offset: 0
0110 is a "good" word because the length of both its runs of 0's is 1.
Words of the form 11...1 are good words because the condition is vacuously satisfied.
a(5) = 24 because there are 32 length 5 binary words but we do not count: 00010, 00101, 00110, 01000, 01001, 01100, 10010, 10100.
For distinct instead of equal lengths we have
A384175, complement
A384176.
For anti-runs instead of runs we have
A384889, for partitions
A384888.
For permutations instead of subsets we have
A384892, distinct instead of equal
A384891.
The complement is counted by
A385214.
A034839 counts subsets by number of maximal runs, for strict partitions
A116674.
A384887 counts partitions with equal lengths of gapless runs, distinct
A384884.
-
a:= n-> 1 + add(add((d-> binomial(d+j, d))(n-(i*j-1))
, j=1..iquo(n+1, i)), i=2..n+1):
seq(a(n), n=0..50); # Alois P. Heinz, Jun 11 2014
-
nn=30;Prepend[Map[Total,Transpose[Table[Drop[CoefficientList[Series[ (1+x^k)/(1-x-x^(k+1))-1/(1-x),{x,0,nn}],x],1],{k,1,nn}]]],0]+1
Table[Length[Select[Subsets[Range[n]],SameQ@@Length/@Split[#,#2==#1+1&]&]],{n,0,10}] (* Gus Wiseman, Jun 23 2025 *)
A384879
Numbers whose binary indices have all distinct lengths of maximal anti-runs (increasing by more than 1).
Original entry on oeis.org
1, 2, 4, 5, 8, 9, 10, 11, 13, 16, 17, 18, 19, 20, 21, 22, 25, 26, 32, 33, 34, 35, 36, 37, 38, 40, 41, 42, 43, 44, 49, 50, 52, 53, 64, 65, 66, 67, 68, 69, 70, 72, 73, 74, 75, 76, 80, 81, 82, 83, 84, 85, 86, 88, 97, 98, 100, 101, 104, 105, 106, 128, 129, 130
Offset: 1
The binary indices of 813 are {1,3,4,6,9,10}, with maximal anti-runs ((1,3),(4,6,9),(10)), with lengths (2,3,1), so 813 is in the sequence.
The terms together with their binary expansions and binary indices begin:
1: 1 ~ {1}
2: 10 ~ {2}
4: 100 ~ {3}
5: 101 ~ {1,3}
8: 1000 ~ {4}
9: 1001 ~ {1,4}
10: 1010 ~ {2,4}
11: 1011 ~ {1,2,4}
13: 1101 ~ {1,3,4}
16: 10000 ~ {5}
17: 10001 ~ {1,5}
18: 10010 ~ {2,5}
19: 10011 ~ {1,2,5}
20: 10100 ~ {3,5}
21: 10101 ~ {1,3,5}
22: 10110 ~ {2,3,5}
25: 11001 ~ {1,4,5}
26: 11010 ~ {2,4,5}
A098859 counts Wilf partitions (distinct multiplicities), complement
A336866.
A356606 counts strict partitions without a neighborless part, complement
A356607.
Cf.
A023758,
A044813,
A048793,
A164707,
A242882,
A243815,
A325325,
A328592,
A384879,
A384884,
A384886,
A384893.
-
bpe[n_]:=Join@@Position[Reverse[IntegerDigits[n,2]],1];
Select[Range[100],UnsameQ@@Length/@Split[bpe[#],#2!=#1+1&]&]
A384880
Number of strict integer partitions of n with all distinct lengths of maximal anti-runs (decreasing by more than 1).
Original entry on oeis.org
1, 1, 1, 1, 2, 2, 3, 4, 6, 6, 9, 10, 12, 15, 18, 21, 25, 30, 34, 41, 46, 55, 63, 75, 85, 99, 114, 133, 152, 178, 201, 236, 269, 308, 352, 404, 460, 525, 594, 674, 763, 865, 974, 1098, 1236, 1385, 1558, 1745, 1952, 2181, 2435, 2712, 3026, 3363, 3740, 4151, 4612
Offset: 0
The strict partition y = (10,7,6,4,2,1) has maximal anti-runs ((10,7),(6,4,2),(1)), with lengths (2,3,1), so y is counted under a(30).
The a(1) = 1 through a(14) = 18 partitions (A-E = 10-14):
1 2 3 4 5 6 7 8 9 A B C D E
31 41 42 52 53 63 64 74 75 85 86
51 61 62 72 73 83 84 94 95
421 71 81 82 92 93 A3 A4
431 531 91 A1 A2 B2 B3
521 621 532 542 B1 C1 C2
541 632 642 643 D1
631 641 651 652 653
721 731 732 742 743
821 741 751 752
831 832 761
921 841 842
931 851
A21 932
6421 941
A31
B21
7421
For subsets instead of strict partitions we have
A384177.
For runs instead of anti-runs we have
A384178.
This is the strict case of
A384885.
A047993 counts partitions with max part = length.
-
Table[Length[Select[IntegerPartitions[n],UnsameQ@@#&&UnsameQ@@Length/@Split[#,#2<#1-1&]&]],{n,0,30}]
A384178
Number of strict integer partitions of n with all distinct lengths of maximal runs (decreasing by 1).
Original entry on oeis.org
1, 1, 1, 2, 1, 2, 2, 3, 3, 4, 5, 6, 6, 8, 8, 10, 11, 13, 13, 16, 15, 19, 19, 23, 22, 26, 28, 31, 35, 39, 37, 47, 51, 52, 60, 65, 67, 78, 85, 86, 99, 108, 110, 127, 136, 138, 159, 170, 171, 196, 209, 213, 240, 257, 260, 292, 306, 313, 350, 371, 369, 417, 441
Offset: 0
The strict partition y = (9,7,6,5,2,1) has maximal runs ((9),(7,6,5),(2,1)), with lengths (1,3,2), so y is counted under a(30).
The a(1) = 1 through a(14) = 8 strict partitions (A-E = 10-14):
1 2 3 4 5 6 7 8 9 A B C D E
21 32 321 43 431 54 532 65 543 76 653
421 521 432 541 542 651 643 743
621 721 632 732 652 761
4321 821 921 832 932
5321 6321 A21 B21
5431 5432
7321 8321
For subsets instead of strict partitions we have
A384175, complement
A384176.
For anti-runs instead of runs we have
A384880.
This is the strict version of
A384884.
For equal instead of distinct lengths we have
A384886.
A047993 counts partitions with max part = length.
-
Table[Length[Select[IntegerPartitions[n],UnsameQ@@#&&UnsameQ@@Length/@Split[#,#1==#2+1&]&]],{n,0,30}]
A384887
Number of integer partitions of n with all equal lengths of maximal gapless runs (decreasing by 0 or 1).
Original entry on oeis.org
1, 1, 2, 3, 5, 6, 9, 10, 14, 18, 21, 26, 35, 39, 46, 58, 68, 79, 97, 111, 131, 155, 177, 206, 246, 278, 318, 373, 423, 483, 563, 632, 722, 827, 931, 1058, 1209, 1354, 1528, 1736, 1951, 2188, 2475, 2762, 3097, 3488, 3886, 4342, 4876, 5414, 6038, 6741, 7482
Offset: 0
The partition y = (6,5,5,5,3,3,2,1) has maximal gapless runs ((6,5,5,5),(3,3,2,1)), with lengths (4,4), so y is counted under a(30).
The a(1) = 1 through a(8) = 14 partitions:
(1) (2) (3) (4) (5) (6) (7) (8)
(11) (21) (22) (32) (33) (43) (44)
(111) (31) (41) (42) (52) (53)
(211) (221) (51) (61) (62)
(1111) (2111) (222) (322) (71)
(11111) (321) (2221) (332)
(2211) (3211) (2222)
(21111) (22111) (3221)
(111111) (211111) (3311)
(1111111) (22211)
(32111)
(221111)
(2111111)
(11111111)
For distinct instead of equal lengths we have
A384884.
For subsets instead of strict partitions we have
A243815.
Without counting decreases by 0 we get
A384904.
A098859 counts Wilf partitions (distinct multiplicities), complement
A336866.
A355394 counts partitions without a neighborless part, singleton case
A355393.
A356236 counts partitions with a neighborless part, singleton case
A356235.
A356606 counts strict partitions without a neighborless part, complement
A356607.
Cf.
A008284,
A044813,
A047993,
A325324,
A325325,
A356226,
A356230,
A356233,
A356234,
A384175,
A384177,
A384880.
-
Table[Length[Select[IntegerPartitions[n],SameQ@@Length/@Split[#,#2>=#1-1&]&]],{n,0,15}]
A384885
Number of integer partitions of n with all distinct lengths of maximal anti-runs (decreasing by more than 1).
Original entry on oeis.org
1, 1, 1, 1, 2, 3, 4, 6, 8, 9, 13, 15, 18, 22, 28, 31, 38, 45, 53, 62, 74, 86, 105, 123, 146, 171, 208, 242, 290, 340, 399, 469, 552, 639, 747, 862, 999, 1150, 1326, 1514, 1736, 1979, 2256, 2560, 2909, 3283, 3721, 4191, 4726, 5311, 5973, 6691, 7510, 8396, 9395
Offset: 0
The partition y = (8,6,3,3,3,1) has maximal anti-runs ((8,6,3),(3),(3,1)), with lengths (3,1,2), so y is counted under a(24).
The partition z = (8,6,5,3,3,1) has maximal anti-runs ((8,6),(5,3),(3,1)), with lengths (2,2,2), so z is not counted under a(26).
The a(1) = 1 through a(9) = 9 partitions:
(1) (2) (3) (4) (5) (6) (7) (8) (9)
(3,1) (4,1) (4,2) (5,2) (5,3) (6,3)
(3,1,1) (5,1) (6,1) (6,2) (7,2)
(4,1,1) (3,3,1) (7,1) (8,1)
(4,2,1) (4,2,2) (4,4,1)
(5,1,1) (4,3,1) (5,2,2)
(5,2,1) (5,3,1)
(6,1,1) (6,2,1)
(7,1,1)
For subsets instead of strict partitions we have
A384177, for runs
A384175.
For equal instead of distinct lengths we have
A384888, for runs
A384887.
A098859 counts Wilf partitions (distinct multiplicities), complement
A336866.
A355394 counts partitions without a neighborless part, singleton case
A355393.
A356236 counts partitions with a neighborless part, singleton case
A356235.
A356606 counts strict partitions without a neighborless part, complement
A356607.
Cf.
A008284,
A047966,
A242882,
A287170,
A325324,
A325325,
A329739,
A356226,
A356230,
A356234,
A384886.
-
Table[Length[Select[IntegerPartitions[n],UnsameQ@@Length/@Split[#,#2<#1-1&]&]],{n,0,15}]
Showing 1-10 of 20 results.
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