A375405
Number of integer partitions of n with a repeated part other than the least.
Original entry on oeis.org
0, 0, 0, 0, 0, 1, 1, 3, 5, 8, 13, 20, 29, 42, 62, 83, 117, 158, 214, 283, 377, 488, 641, 823, 1058, 1345, 1714, 2154, 2713, 3387, 4222, 5230, 6474, 7959, 9782, 11956, 14591, 17737, 21529, 26026, 31422, 37811, 45425, 54418, 65097, 77652, 92510, 109943, 130468
Offset: 0
The a(0) = 0 through a(10) = 13 partitions:
. . . . . (221) (2211) (331) (332) (441) (442)
(2221) (3221) (3321) (3322)
(22111) (3311) (4221) (3331)
(22211) (22221) (4411)
(221111) (32211) (5221)
(33111) (32221)
(222111) (33211)
(2211111) (42211)
(222211)
(322111)
(331111)
(2221111)
(22111111)
The complement for maxima instead of minima is
A034296.
These partitions have ranks
A375397.
A055887 counts sequences of partitions with total sum n.
A375128 lists minima of maximal anti-runs of prime indices, sums
A374706.
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Table[Length[Select[IntegerPartitions[n], !SameQ@@Min/@Split[#,UnsameQ]&]],{n,0,30}]
- or -
Table[Length[Select[IntegerPartitions[n], !UnsameQ@@DeleteCases[#,Min@@#]&]],{n,0,30}]
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A_x(N) = {my(x='x+O('x^N), f=sum(i=1,N,sum(j=i+1,N-i, ((x^(i+(2*j)))/(1-x^i))*prod(k=i+1,N-i-(2*j), if(kJohn Tyler Rascoe, Aug 21 2024
A367402
Number of integer partitions of n whose semi-sums cover an interval of positive integers.
Original entry on oeis.org
1, 1, 2, 3, 5, 6, 9, 10, 13, 17, 20, 26, 31, 38, 44, 58, 64, 81, 95, 116, 137, 166, 192, 233, 278, 330, 385, 459, 542, 636, 759, 879, 1038, 1211, 1418, 1656, 1942, 2242, 2618, 3029, 3535, 4060, 4735, 5429, 6299, 7231, 8346, 9556, 11031, 12593, 14482, 16525
Offset: 0
The partition y = (3,2,1,1) has semi-sums {2,3,4,5}, which is an interval, so y is counted under a(7).
The a(1) = 1 through a(8) = 13 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) (22211)
(1111111) (32111)
(221111)
(2111111)
(11111111)
The complement is counted by
A367403.
A000009 counts partitions covering an initial interval, ranks
A055932.
A086971 counts semi-sums of prime indices.
A261036 counts complete partitions by maximum.
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Table[Length[Select[IntegerPartitions[n], (d=Total/@Subsets[#,{2}];If[d=={}, {}, Range[Min@@d,Max@@d]]==Union[d])&]], {n,0,15}]
A367403
Number of integer partitions of n whose semi-sums do not cover an interval of positive integers.
Original entry on oeis.org
0, 0, 0, 0, 0, 1, 2, 5, 9, 13, 22, 30, 46, 63, 91, 118, 167, 216, 290, 374, 490, 626, 810, 1022, 1297, 1628, 2051, 2551, 3176, 3929, 4845, 5963, 7311, 8932, 10892, 13227, 16035, 19395, 23397, 28156, 33803, 40523, 48439, 57832, 68876, 81903, 97212, 115198
Offset: 0
The a(0) = 0 through a(9) = 13 partitions:
. . . . . (311) (411) (331) (422) (441)
(3111) (421) (431) (522)
(511) (521) (531)
(4111) (611) (621)
(31111) (3311) (711)
(4211) (4311)
(5111) (5211)
(41111) (6111)
(311111) (33111)
(42111)
(51111)
(411111)
(3111111)
The complement is counted by
A367402.
A000009 counts partitions covering an initial interval, ranks
A055932.
A086971 counts semi-sums of prime indices.
A261036 counts complete partitions by maximum.
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Table[Length[Select[IntegerPartitions[n], (d=Total/@Subsets[#,{2}];If[d=={}, {}, Range[Min@@d,Max@@d]]!=Union[d])&]], {n,0,15}]
A367410
Number of strict integer partitions of n whose semi-sums cover an interval of positive integers.
Original entry on oeis.org
1, 1, 1, 2, 2, 3, 4, 4, 4, 6, 6, 7, 7, 8, 8, 11, 9, 11, 11, 12, 12, 15, 14, 15, 16, 16, 16, 19, 18, 19, 22, 21, 21, 24, 22, 25, 26, 26, 26, 30, 28, 29, 32, 31, 32, 37, 35, 36, 38, 39, 39, 43, 42, 43, 47, 46, 49, 51, 52, 51, 58
Offset: 0
The partition y = (4,2,1) has semi-sums {3,5,6} which are missing 4, so y is not counted under a(7).
The a(1) = 1 through a(9) = 6 partitions:
(1) (2) (3) (4) (5) (6) (7) (8) (9)
(2,1) (3,1) (3,2) (4,2) (4,3) (5,3) (5,4)
(4,1) (5,1) (5,2) (6,2) (6,3)
(3,2,1) (6,1) (7,1) (7,2)
(8,1)
(4,3,2)
For parts instead of sums we have
A001227:
The non-strict complement is
A367403.
The complement is counted by
A367411.
A000009 counts partitions covering an initial interval, ranks
A055932.
A046663 counts partitions w/o submultiset summing to k, strict
A365663.
A365543 counts partitions w/ submultiset summing to k, strict
A365661.
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Table[Length[Select[IntegerPartitions[n], UnsameQ@@#&&(d=Total/@Subsets[#,{2}]; If[d=={},{}, Range[Min@@d, Max@@d]]==Union[d])&]], {n,0,30}]
A367411
Number of strict integer partitions of n whose semi-sums do not cover an interval of positive integers.
Original entry on oeis.org
0, 0, 0, 0, 0, 0, 0, 1, 2, 2, 4, 5, 8, 10, 14, 16, 23, 27, 35, 42, 52, 61, 75, 89, 106, 126, 149, 173, 204, 237, 274, 319, 369, 424, 490, 560, 642, 734, 838, 952, 1085, 1231, 1394, 1579, 1784, 2011, 2269, 2554, 2872, 3225, 3619, 4054, 4540, 5077, 5671, 6332
Offset: 0
The partition y = (4,2,1) has semi-sums {3,5,6} which are missing 4, so y is counted under a(7).
The a(7) = 1 through a(13) = 10 partitions:
(4,2,1) (4,3,1) (5,3,1) (5,3,2) (5,4,2) (6,4,2) (6,4,3)
(5,2,1) (6,2,1) (5,4,1) (6,3,2) (6,5,1) (6,5,2)
(6,3,1) (6,4,1) (7,3,2) (7,4,2)
(7,2,1) (7,3,1) (7,4,1) (7,5,1)
(8,2,1) (8,3,1) (8,3,2)
(9,2,1) (8,4,1)
(5,4,2,1) (9,3,1)
(6,3,2,1) (10,2,1)
(6,4,2,1)
(7,3,2,1)
For parts instead of sums we have
A238007:
The non-strict complement is
A367402.
The complement is counted by
A367410.
A000009 counts partitions covering an initial interval, ranks
A055932.
A046663 counts partitions w/o submultiset summing to k, strict
A365663.
A365543 counts partitions w/ submultiset summing to k, strict
A365661.
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Table[Length[Select[IntegerPartitions[n], UnsameQ@@#&&(d=Total/@Subsets[#, {2}];If[d=={},{}, Range[Min@@d,Max@@d]]!=Union[d])&]], {n,0,30}]
A239956
Number of partitions p of n such that (number of distinct parts of p) = max(p) - min(p).
Original entry on oeis.org
0, 0, 0, 0, 1, 1, 2, 3, 6, 5, 10, 12, 16, 21, 28, 30, 45, 53, 63, 81, 99, 114, 144, 173, 204, 245, 293, 340, 410, 482, 554, 662, 774, 890, 1044, 1207, 1393, 1619, 1864, 2134, 2464, 2828, 3220, 3701, 4223, 4789, 5474, 6223, 7050, 8004, 9058, 10230, 11579
Offset: 0
a(8) counts these 6 partitions: 53, 431, 422, 4211, 3311, 311111.
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z = 60; d[p_] := d[p] = Length[DeleteDuplicates[p]]; f[p_] := f[p] = Max[p] - Min[p]; g[n_] := g[n] = IntegerPartitions[n];
Table[Count[g[n], p_ /; d[p] < f[p]], {n, 0, z}] (* A239954 *)
Table[Count[g[n], p_ /; d[p] <= f[p]], {n, 0, z}] (* A239955 *)
Table[Count[g[n], p_ /; d[p] == f[p]], {n, 0, z}] (* this sequence *)
Table[Count[g[n], p_ /; d[p] > f[p]], {n, 0, z}] (* A034296 *)
Table[Count[g[n], p_ /; d[p] >= f[p]], {n, 0, z}] (* A239958 *)
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A_x(N) = {my(x='x+O('x^N), g = sum(m=1,N, sum(i=m+2,N, x^(i+m)/((1-x^i)*(1-x^m)) * sum(j=m+1,i-1, (1-x^j)/(x^j) * prod(k=m+1,i-1, (x^k/(1-x^k)))))));
concat([0,0,0,0],Vec(g))}
A_x(51) \\ John Tyler Rascoe, Mar 16 2024
A239958
Number of partitions p of n such that (number of distinct parts of p) >= max(p) - min(p).
Original entry on oeis.org
1, 1, 2, 3, 5, 6, 9, 11, 16, 18, 25, 30, 39, 47, 59, 69, 89, 105, 126, 153, 184, 215, 259, 307, 362, 426, 501, 583, 687, 800, 923, 1080, 1252, 1439, 1666, 1917, 2202, 2533, 2900, 3311, 3792, 4326, 4915, 5605, 6366, 7205, 8180, 9259, 10458, 11815, 13322
Offset: 0
a(6) counts all of the 15 partitions of 7 except these 4: 61, 52, 511, 1111111.
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z = 60; d[p_] := d[p] = Length[DeleteDuplicates[p]]; f[p_] := f[p] = Max[p] - Min[p]; g[n_] := g[n] = IntegerPartitions[n];
Table[Count[g[n], p_ /; d[p] < f[p]], {n, 0, z}] (*A239954*)
Table[Count[g[n], p_ /; d[p] <= f[p]], {n, 0, z}] (*A239955*)
Table[Count[g[n], p_ /; d[p] == f[p]], {n, 0, z}] (*A239956*)
Table[Count[g[n], p_ /; d[p] > f[p]], {n, 0, z}] (*A034296*)
Table[Count[g[n], p_ /; d[p] >= f[p]], {n, 0, z}] (*A239958*)
ndpQ[p_]:=Module[{prt=Union[p]},Length[prt]>=(Max[prt]-Min[prt])]; Table[Length[Select[ IntegerPartitions[ n],ndpQ]],{n,0,50}] (* Harvey P. Dale, Dec 31 2023 *)
A356846
Number of integer compositions of n into parts not covering an interval of positive integers.
Original entry on oeis.org
0, 0, 0, 0, 2, 5, 11, 25, 57, 115, 236, 482, 978, 1986, 4003, 8033, 16150, 32402, 64943, 130207, 260805, 522123, 1045168, 2091722, 4185431, 8374100, 16753538, 33515122, 67042865, 134106640, 268246886, 536549760, 1073194999, 2146553011, 4293391411, 8587283895
Offset: 0
The a(0) = 0 through a(6) = 8 compositions:
. . . . (13) (14) (15)
(31) (41) (24)
(113) (42)
(131) (51)
(311) (114)
(141)
(411)
(1113)
(1131)
(1311)
(3111)
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gappyQ[m_]:=And[m!={},Union[m]!=Range[Min[m],Max[m]]];
Table[Length[Select[Join@@Permutations/@IntegerPartitions[n],gappyQ]],{n,0,15}]
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