A364350
Number of strict integer partitions of n such that no part can be written as a nonnegative linear combination of the others.
Original entry on oeis.org
1, 1, 1, 1, 1, 2, 1, 3, 2, 3, 3, 5, 3, 6, 5, 7, 6, 9, 7, 11, 10, 14, 12, 16, 15, 20, 17, 24, 22, 27, 29, 32, 30, 41, 36, 49, 45, 50, 52, 65, 63, 70, 77, 80, 83, 104, 98, 107, 116, 126, 134, 152, 148, 162, 180, 196, 195, 227, 227, 238, 272, 271, 293, 333, 325
Offset: 0
The a(16) = 6 through a(22) = 12 strict partitions:
(16) (17) (18) (19) (20) (21) (22)
(9,7) (9,8) (10,8) (10,9) (11,9) (12,9) (13,9)
(10,6) (10,7) (11,7) (11,8) (12,8) (13,8) (14,8)
(11,5) (11,6) (13,5) (12,7) (13,7) (15,6) (15,7)
(13,3) (12,5) (14,4) (13,6) (14,6) (16,5) (16,6)
(7,5,4) (13,4) (7,6,5) (14,5) (17,3) (17,4) (17,5)
(14,3) (8,7,3) (15,4) (8,7,5) (19,2) (18,4)
(15,2) (16,3) (9,6,5) (11,10) (19,3)
(7,6,4) (17,2) (9,7,4) (8,7,6) (12,10)
(8,6,5) (11,5,4) (9,7,5) (9,7,6)
(9,6,4) (10,7,4) (9,8,5)
(10,8,3) (7,6,5,4)
(11,6,4)
(11,7,3)
For sums of subsets instead of combinations of partitions we have
A151897.
For subsets instead of partitions we have
A326083, complement
A364914.
A more strict variation is
A364915.
The case of all positive coefficients is
A365006.
A364912 counts linear combinations of partitions of k.
Cf.
A007865,
A085489,
A237113,
A275972,
A363226,
A364272,
A364533,
A364910,
A364911,
A365002,
A365004.
-
combs[n_,y_]:=With[{s=Table[{k,i},{k,y},{i,0,Floor[n/k]}]},Select[Tuples[s],Total[Times@@@#]==n&]];
Table[Length[Select[IntegerPartitions[n],UnsameQ@@#&&And@@Table[combs[#[[k]],Delete[#,k]]=={},{k,Length[#]}]&]],{n,0,15}]
-
from sympy.utilities.iterables import partitions
def A364350(n):
if n <= 1: return 1
alist, c = [set(tuple(sorted(set(p))) for p in partitions(i)) for i in range(n)], 1
for p in partitions(n,k=n-1):
if max(p.values(),default=0)==1:
s = set(p)
if not any(set(t).issubset(s-{q}) for q in s for t in alist[q]):
c += 1
return c # Chai Wah Wu, Sep 23 2023
A364272
Number of strict integer partitions of n containing the sum of some subset of the parts. A variation of sum-full strict partitions.
Original entry on oeis.org
0, 0, 0, 0, 0, 0, 1, 0, 1, 0, 3, 1, 4, 3, 8, 6, 11, 10, 17, 16, 26, 25, 39, 39, 54, 60, 82, 84, 116, 126, 160, 177, 222, 242, 302, 337, 402, 453, 542, 601, 722, 803, 936, 1057, 1234, 1373, 1601, 1793, 2056, 2312, 2658, 2950, 3395, 3789, 4281, 4814, 5452, 6048
Offset: 0
The a(6) = 1 through a(16) = 11 partitions (A=10):
(321) . (431) . (532) (5321) (642) (5431) (743) (6432) (853)
(541) (651) (6421) (752) (6531) (862)
(4321) (5421) (7321) (761) (7431) (871)
(6321) (5432) (7521) (6532)
(6431) (9321) (6541)
(6521) (54321) (7432)
(7421) (7621)
(8321) (8431)
(8521)
(A321)
(64321)
The linear combination-free version is
A364350.
-
Table[Length[Select[IntegerPartitions[n], UnsameQ@@#&&Intersection[#, Total/@Subsets[#,{2,Length[#]}]]!={}&]],{n,0,30}]
A093971
Number of sum-full subsets of {1,...,n}; subsets A such that there is a solution to x+y=z for x,y,z in A.
Original entry on oeis.org
0, 1, 2, 7, 16, 40, 86, 195, 404, 873, 1795, 3727, 7585, 15537, 31368, 63582, 127933, 257746, 517312, 1038993, 2081696, 4173322, 8355792, 16731799, 33484323, 67014365, 134069494, 268234688, 536562699, 1073326281, 2146849378, 4294117419, 8588623348, 17178130162
Offset: 1
The a(1) = 0 through a(5) = 16 subsets:
. {1,2} {1,2} {1,2} {1,2}
{1,2,3} {2,4} {2,4}
{1,2,3} {1,2,3}
{1,2,4} {1,2,4}
{1,3,4} {1,2,5}
{2,3,4} {1,3,4}
{1,2,3,4} {1,4,5}
{2,3,4}
{2,3,5}
{2,4,5}
{1,2,3,4}
{1,2,3,5}
{1,2,4,5}
{1,3,4,5}
{2,3,4,5}
{1,2,3,4,5}
The complement is counted by
A007865.
The non-binary version w/o re-usable parts is
A364534, complement
A151897.
The version for partitions is
A363225:
- non-binary without re-usable parts
A237668.
The complement for partitions is
A364345:
- non-binary without re-usable parts
A237667.
-
Table[Length[Select[Subsets[Range[n]],Intersection[#,Total/@Tuples[#,2]]!={}&]],{n,0,10}] (* Gus Wiseman, Aug 14 2023 *)
A088809
Number of subsets of {1, ..., n} that are not sum-free.
Original entry on oeis.org
0, 0, 0, 1, 3, 10, 27, 67, 154, 350, 763, 1638, 3450, 7191, 14831, 30398, 61891, 125557, 253841, 511818, 1029863, 2069341, 4153060, 8327646, 16687483, 33422562, 66916342, 133936603, 268026776, 536277032, 1072886163, 2146245056, 4293187682, 8587371116
Offset: 0
From _Gus Wiseman_, Aug 10 2023: (Start)
The set S = {1,3,6,8} has pair-sums {4,7,9,11,14}, which are all missing from S, so it is not counted under a(8).
The set {1,4,6,7} has pair-sum 1 + 6 = 7, so is counted under a(7).
The a(1) = 0 through a(5) = 10 sets:
. . {1,2,3} {1,2,3} {1,2,3}
{1,3,4} {1,3,4}
{1,2,3,4} {1,4,5}
{2,3,5}
{1,2,3,4}
{1,2,3,5}
{1,2,4,5}
{1,3,4,5}
{2,3,4,5}
{1,2,3,4,5}
(End)
The complement for partitions is
A236912:
The version for partitions is
A237113:
Cf.
A000079,
A007865,
A050291,
A051026,
A103580,
A288728,
A326020,
A326080,
A326083,
A364272,
A364349.
-
Table[Length[Select[Subsets[Range[n]],Intersection[#,Total/@Subsets[#,{2}]]!={}&]],{n,0,10}] (* Gus Wiseman, Aug 10 2023 *)
A236912
Number of partitions of n such that no part is a sum of two other parts.
Original entry on oeis.org
1, 1, 2, 3, 4, 6, 8, 12, 14, 20, 25, 34, 40, 54, 64, 85, 98, 127, 149, 189, 219, 277, 316, 395, 456, 557, 638, 778, 889, 1070, 1226, 1461, 1667, 1978, 2250, 2645, 3019, 3521, 3997, 4652, 5267, 6093, 6909, 7943, 8982, 10291, 11609, 13251, 14947, 16984, 19104
Offset: 0
Of the 11 partitions of 6, only these 3 include a part that is a sum of two other parts: [3,2,1], [2,2,1,1], [2,1,1,1,1]. Thus, a(6) = 11 - 3 = 8.
From _Gus Wiseman_, Aug 09 2023: (Start)
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)
(1111) (221) (51) (61) (62)
(311) (222) (322) (71)
(11111) (411) (331) (332)
(3111) (421) (521)
(111111) (511) (611)
(2221) (2222)
(4111) (3311)
(31111) (5111)
(1111111) (41111)
(311111)
(11111111)
(End)
The (strict) version for linear combinations of parts is
A364350.
These partitions have ranks
A364461.
-
z = 20; t = Map[Count[Map[Length[Cases[Map[Total[#] &, Subsets[#, {2}]], Apply[Alternatives, #]]] &, IntegerPartitions[#]], 0] &, Range[z]] (* A236912 *)
u = PartitionsP[Range[z]] - t (* A237113, Peter J. C. Moses, Feb 03 2014 *)
Table[Length[Select[IntegerPartitions[n],Intersection[#,Total/@Subsets[#,{2}]]=={}&]],{n,0,15}] (* Gus Wiseman, Aug 09 2023 *)
A237667
Number of partitions of n such that no part is a sum of two or more other parts.
Original entry on oeis.org
1, 1, 2, 3, 4, 6, 7, 11, 12, 17, 19, 29, 28, 41, 42, 61, 61, 87, 85, 120, 117, 160, 156, 224, 216, 288, 277, 380, 363, 483, 474, 622, 610, 783, 755, 994, 986, 1235, 1191, 1549, 1483, 1876, 1865, 2306, 2279, 2806, 2732, 3406, 3413, 4091, 4013, 4991, 4895, 5872
Offset: 0
For n = 6, the nonqualifiers are 123, 1113, 1122, 11112, leaving a(6) = 7.
From _Gus Wiseman_, Aug 09 2023: (Start)
The partition y = (5,3,1,1) has submultiset (3,1,1) with sum in y, so is not counted under a(10).
The partition y = (5,3,3,1) has no non-singleton submultiset with sum in y, so is counted under a(12).
The a(1) = 1 through a(8) = 12 partitions:
(1) (2) (3) (4) (5) (6) (7) (8)
(11) (21) (22) (32) (33) (43) (44)
(111) (31) (41) (42) (52) (53)
(1111) (221) (51) (61) (62)
(311) (222) (322) (71)
(11111) (411) (331) (332)
(111111) (421) (521)
(511) (611)
(2221) (2222)
(4111) (3311)
(1111111) (5111)
(11111111)
(End)
These partitions have ranks
A364531.
-
Map[Count[Map[MemberQ[#,Apply[Alternatives,Map[Apply[Plus,#]&, DeleteDuplicates[DeleteCases[Subsets[#],?(Length[#]<2&)]]]]]&, IntegerPartitions[#]],False]&,Range[20]] (* _Peter J. C. Moses, Feb 10 2014 *)
Table[Length[Select[IntegerPartitions[n],Intersection[#,Total/@Subsets[#,{2,Length[#]}]]=={}&]],{n,0,15}] (* Gus Wiseman, Aug 09 2023 *)
A237668
Number of partitions of n such that some part is a sum of two or more other parts.
Original entry on oeis.org
0, 0, 0, 0, 1, 1, 4, 4, 10, 13, 23, 27, 49, 60, 93, 115, 170, 210, 300, 370, 510, 632, 846, 1031, 1359, 1670, 2159, 2630, 3355, 4082, 5130, 6220, 7739, 9360, 11555, 13889, 16991, 20402, 24824, 29636, 35855, 42707, 51309, 60955, 72896, 86328, 102826, 121348
Offset: 0
a(6) = 4 counts these partitions: 123, 1113, 1122, 11112.
From _Gus Wiseman_, Aug 12 2023: (Start)
The a(0) = 0 through a(9) = 13 partitions:
. . . . (211) (2111) (321) (3211) (422) (3321)
(2211) (22111) (431) (4221)
(3111) (31111) (3221) (4311)
(21111) (211111) (4211) (5211)
(22211) (32211)
(32111) (33111)
(41111) (42111)
(221111) (222111)
(311111) (321111)
(2111111) (411111)
(2211111)
(3111111)
(21111111)
(End)
These partitions have ranks
A364532.
For subsets instead of partitions we have
A364534, complement
A151897.
A299701 counts distinct subset-sums of prime indices.
-
z = 20; m = Map[Count[Map[MemberQ[#, Apply[Alternatives, Map[Apply[Plus, #] &, DeleteDuplicates[DeleteCases[Subsets[#], _?(Length[#] < 2 &)]]]]] &, IntegerPartitions[#]], False] &, Range[z]]; PartitionsP[Range[z]] - m
(* Peter J. C. Moses, Feb 10 2014 *)
Table[Length[Select[IntegerPartitions[n],Intersection[#,Total/@Subsets[#,{2,Length[#]}]]!={}&]],{n,0,15}] (* Gus Wiseman, Aug 12 2023 *)
A364534
Number of subsets of {1..n} containing some element equal to the sum of two or more distinct other elements. A variation of sum-full subsets without re-used elements.
Original entry on oeis.org
0, 0, 0, 1, 3, 10, 27, 68, 156, 357, 775, 1667, 3505, 7303, 15019, 30759, 62489, 126619, 255542, 514721, 1034425, 2076924, 4164650, 8346306, 16715847, 33467324, 66982798, 134040148, 268179417, 536510608, 1073226084, 2146759579, 4293930436, 8588485846, 17177799658
Offset: 0
The a(0) = 0 through a(5) = 10 subsets:
. . . {1,2,3} {1,2,3} {1,2,3}
{1,3,4} {1,3,4}
{1,2,3,4} {1,4,5}
{2,3,5}
{1,2,3,4}
{1,2,3,5}
{1,2,4,5}
{1,3,4,5}
{2,3,4,5}
{1,2,3,4,5}
The complement is counted by
A151897.
A236912 counts sum-free partitions w/o re-used parts, complement
A237113.
Cf.
A007865,
A093971,
A323092,
A325862,
A326083,
A363225,
A364345,
A364346,
A364348,
A364350,
A364533,
A364670.
-
Table[Length[Select[Subsets[Range[n]],Intersection[#,Total/@Subsets[#,{2,Length[#]}]]!={}&]],{n,0,10}]
A364914
Number of subsets of {1..n} such that some element can be written as a nonnegative linear combination of the others.
Original entry on oeis.org
0, 0, 1, 3, 9, 20, 48, 101, 219, 454, 944, 1917, 3925, 7915, 16004, 32188, 64751, 129822, 260489, 521672, 1045060, 2091808, 4187047, 8377255, 16762285, 33531228, 67077485, 134170217, 268371678, 536772231, 1073611321, 2147282291, 4294697258, 8589527163, 17179321094
Offset: 0
The set {3,4,5,17} has 17 = 1*3 + 1*4 + 2*5, so is counted under a(17).
The a(0) = 0 through a(5) = 20 subsets:
. . {1,2} {1,2} {1,2} {1,2}
{1,3} {1,3} {1,3}
{1,2,3} {1,4} {1,4}
{2,4} {1,5}
{1,2,3} {2,4}
{1,2,4} {1,2,3}
{1,3,4} {1,2,4}
{2,3,4} {1,2,5}
{1,2,3,4} {1,3,4}
{1,3,5}
{1,4,5}
{2,3,4}
{2,3,5}
{2,4,5}
{1,2,3,4}
{1,2,3,5}
{1,2,4,5}
{1,3,4,5}
{2,3,4,5}
{1,2,3,4,5}
The binary version without re-usable parts is
A088809.
The complement without re-usable parts is
A151897.
The complement is counted by
A326083.
The version without re-usable parts is
A364534.
The version for partitions is
A364913.
Cf.
A011782,
A085489,
A103580,
A116861,
A124506,
A237113,
A237668,
A308546,
A324736,
A326020,
A326080,
A364272,
A364349,
A364756.
-
combs[n_,y_]:=With[{s=Table[{k,i},{k,y},{i,0,Floor[n/k]}]},Select[Tuples[s],Total[Times@@@#]==n&]];
Table[Length[Select[Subsets[Range[n]],Or@@Table[combs[#[[k]],Delete[#,k]]!={},{k,Length[#]}]&]],{n,0,10}]
-
from itertools import combinations
from sympy.utilities.iterables import partitions
def A364914(n):
c, mlist = 0, []
for m in range(1,n+1):
t = set()
for p in partitions(m,k=m-1):
t.add(tuple(sorted(p.keys())))
mlist.append([set(d) for d in t])
for k in range(2,n+1):
for w in combinations(range(1,n+1),k):
ws = set(w)
for d in w:
for s in mlist[d-1]:
if s <= ws:
c += 1
break
else:
continue
break
return c # Chai Wah Wu, Nov 17 2023
A363225
Number of integer partitions of n containing three parts (a,b,c) (repeats allowed) such that a + b = c. A variation of sum-full partitions.
Original entry on oeis.org
0, 0, 0, 1, 1, 2, 4, 5, 9, 14, 21, 29, 43, 58, 81, 109, 148, 195, 263, 339, 445, 574, 744, 942, 1209, 1515, 1923, 2399, 3005, 3721, 4629, 5693, 7024, 8589, 10530, 12804, 15596, 18876, 22870, 27538, 33204, 39816, 47766, 57061, 68161, 81099, 96510, 114434, 135634
Offset: 0
The a(3) = 1 through a(9) = 14 partitions:
(21) (211) (221) (42) (421) (422) (63)
(2111) (321) (2221) (431) (432)
(2211) (3211) (521) (621)
(21111) (22111) (3221) (3321)
(211111) (4211) (4221)
(22211) (4311)
(32111) (5211)
(221111) (22221)
(2111111) (32211)
(42111)
(222111)
(321111)
(2211111)
(21111111)
For subsets of {1..n} we have
A093971,
A088809 without re-using parts.
The complement for subsets is
A007865,
A085489 without re-using parts.
For sums of any length > 1 (without re-usable parts) we have
A237668, complement
A237667.
The strict linear combination-free version is
A364350.
-
Table[Length[Select[IntegerPartitions[n],Select[Tuples[#,3],#[[1]]+#[[2]]==#[[3]]&]!={}&]],{n,0,15}]
-
from collections import Counter
from itertools import combinations_with_replacement
from sympy.utilities.iterables import partitions
def A363225(n): return sum(1 for p in partitions(n) if any(q[0]+q[1]==q[2] for q in combinations_with_replacement(sorted(Counter(p).elements()),3))) # Chai Wah Wu, Sep 21 2023
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