A365004
Array read by antidiagonals downwards where A(n,k) is the number of ways to write n as a nonnegative linear combination of an integer partition of k.
Original entry on oeis.org
1, 1, 0, 2, 1, 0, 3, 2, 1, 0, 5, 4, 4, 1, 0, 7, 7, 8, 4, 1, 0, 11, 12, 17, 13, 6, 1, 0, 15, 19, 30, 28, 18, 6, 1, 0, 22, 30, 53, 58, 50, 24, 8, 1, 0, 30, 45, 86, 109, 108, 70, 33, 8, 1, 0, 42, 67, 139, 194, 223, 179, 107, 40, 10, 1, 0, 56, 97, 213, 328, 420, 394, 286, 143, 50, 10, 1, 0
Offset: 0
Array begins:
1 1 2 3 5 7 11
0 1 2 4 7 12 19
0 1 4 8 17 30 53
0 1 4 13 28 58 109
0 1 6 18 50 108 223
0 1 6 24 70 179 394
0 1 8 33 107 286 696
0 1 8 40 143 428 1108
0 1 10 50 199 628 1754
0 1 10 61 254 882 2622
0 1 12 72 332 1215 3857
0 1 12 84 410 1624 5457
0 1 14 99 517 2142 7637
The A(4,2) = 6 ways:
2*2
0*1+4*1
1*1+3*1
2*1+2*1
3*1+1*1
4*1+0*1
Column k = 2 is
A052928 except initial terms.
The case of strict integer partitions is
A116861.
The transpose is
A364912, also the positive version.
A364350 counts combination-free strict partitions, complement
A364839.
A364913 counts combination-full partitions.
-
b:= proc(n, i, m) option remember; `if`(n=0, `if`(m=0, 1, 0),
`if`(i<1, 0, b(n, i-1, m)+add(b(n-i, min(i, n-i), m-i*j), j=0..m/i)))
end:
A:= (n, k)-> b(k$2, n):
seq(seq(A(n, d-n), n=0..d), d=0..12); # Alois P. Heinz, Jan 28 2024
-
nn=5;
combs[n_,y_]:=With[{s=Table[{k,i},{k,y},{i,0,Floor[n/k]}]},Select[Tuples[s],Total[Times@@@#]==n&]];
tabv=Table[Length[Join@@Table[combs[n,ptn],{ptn,IntegerPartitions[k]}]],{n,0,nn},{k,0,nn}]
Table[tabv[[k+1,n-k+1]],{n,0,nn},{k,0,n}]
A364467
Number of integer partitions of n where some part is the difference of two consecutive parts.
Original entry on oeis.org
0, 0, 0, 1, 1, 2, 4, 5, 9, 13, 21, 28, 42, 55, 78, 106, 144, 187, 255, 325, 429, 554, 717, 906, 1165, 1460, 1853, 2308, 2899, 3582, 4468, 5489, 6779, 8291, 10173, 12363, 15079, 18247, 22124, 26645, 32147, 38555, 46285, 55310, 66093, 78684, 93674, 111104
Offset: 0
The a(3) = 1 through a(9) = 13 partitions:
(21) (211) (221) (42) (421) (422) (63)
(2111) (321) (2221) (431) (621)
(2211) (3211) (521) (3321)
(21111) (22111) (3221) (4221)
(211111) (4211) (4311)
(22211) (5211)
(32111) (22221)
(221111) (32211)
(2111111) (42111)
(222111)
(321111)
(2211111)
(21111111)
For all differences of pairs parts we have
A363225, complement
A364345.
The complement is counted by
A363260.
These partitions have ranks
A364537.
A325325 counts partitions with distinct first differences.
Cf.
A002865,
A025065,
A093971,
A108917,
A196723,
A229816,
A236912,
A237113,
A237667,
A320347,
A326083.
-
Table[Length[Select[IntegerPartitions[n],Intersection[#,-Differences[#]]!={}&]],{n,0,30}]
-
from collections import Counter
from sympy.utilities.iterables import partitions
def A364467(n): return sum(1 for s,p in map(lambda x: (x[0],tuple(sorted(Counter(x[1]).elements()))), partitions(n,size=True)) if not set(p).isdisjoint({p[i+1]-p[i] for i in range(s-1)})) # Chai Wah Wu, Sep 26 2023
A365045
Number of subsets of {1..n} containing n such that no element can be written as a positive linear combination of the others.
Original entry on oeis.org
0, 1, 1, 2, 4, 11, 23, 53, 111, 235, 483, 988, 1998, 4036, 8114, 16289, 32645, 65389, 130887, 261923, 524014, 1048251, 2096753, 4193832, 8388034, 16776544, 33553622, 67107919, 134216597, 268434140, 536869355, 1073740012, 2147481511, 4294964834, 8589931700
Offset: 0
The subset {3,4,10} has 10 = 2*3 + 1*4 so is not counted under a(10).
The a(0) = 0 through a(5) = 11 subsets:
. {1} {2} {3} {4} {5}
{2,3} {3,4} {2,5}
{2,3,4} {3,5}
{1,2,3,4} {4,5}
{2,4,5}
{3,4,5}
{1,2,3,5}
{1,2,4,5}
{1,3,4,5}
{2,3,4,5}
{1,2,3,4,5}
Without re-usable parts we have
A365071, first differences of
A151897.
A085489 and
A364755 count subsets w/o the sum of two distinct elements.
A088809 and
A364756 count subsets with the sum of two distinct elements.
A364350 counts combination-free strict partitions, complement
A364839.
A364913 counts combination-full partitions.
-
combp[n_,y_]:=With[{s=Table[{k,i},{k,y},{i,1,Floor[n/k]}]},Select[Tuples[s],Total[Times@@@#]==n&]];
Table[Length[Select[Subsets[Range[n]],MemberQ[#,n]&&And@@Table[combp[#[[k]],Union[Delete[#,k]]]=={},{k,Length[#]}]&]],{n,0,10}]
A364536
Number of strict integer partitions of n where some part is a difference of two consecutive parts.
Original entry on oeis.org
0, 0, 0, 1, 0, 0, 2, 1, 2, 2, 5, 4, 6, 6, 9, 11, 16, 17, 23, 25, 30, 38, 48, 55, 65, 78, 92, 106, 127, 146, 176, 205, 230, 277, 315, 366, 421, 483, 552, 640, 727, 829, 950, 1083, 1218, 1408, 1577, 1794, 2017, 2298, 2561, 2919, 3255, 3685, 4116, 4638, 5163
Offset: 0
The a(3) = 1 through a(15) = 11 partitions (A = 10, B = 11, C = 12):
21 . . 42 421 431 63 532 542 84 742 743 A5
321 521 621 541 632 642 841 752 843
631 821 651 A21 761 942
721 5321 921 5431 842 C21
4321 5421 6421 B21 6432
6321 7321 6431 6531
6521 7431
7421 7521
8321 8421
9321
54321
A325325 counts partitions with distinct first-differences, strict
A320347.
-
Table[Length[Select[IntegerPartitions[n],UnsameQ@@#&&Intersection[#,-Differences[#]]!={}&]],{n,0,30}]
-
from collections import Counter
from sympy.utilities.iterables import partitions
def A364536(n): return sum(1 for s,p in map(lambda x: (x[0],tuple(sorted(Counter(x[1]).elements()))), filter(lambda p:max(p[1].values(),default=1)==1,partitions(n,size=True))) if not set(p).isdisjoint({p[i+1]-p[i] for i in range(s-1)})) # Chai Wah Wu, Sep 26 2023
A364537
Heinz numbers of integer partitions where some part is the difference of two consecutive parts.
Original entry on oeis.org
6, 12, 18, 21, 24, 30, 36, 42, 48, 54, 60, 63, 65, 66, 70, 72, 78, 84, 90, 96, 102, 108, 114, 120, 126, 130, 132, 133, 138, 140, 144, 147, 150, 154, 156, 162, 165, 168, 174, 180, 186, 189, 192, 195, 198, 204, 210, 216, 222, 228, 231, 234, 240, 246, 252, 258
Offset: 1
The partition {3,4,5,7} with Heinz number 6545 has first differences (1,1,2) so is not in the sequence.
The terms together with their prime indices begin:
6: {1,2}
12: {1,1,2}
18: {1,2,2}
21: {2,4}
24: {1,1,1,2}
30: {1,2,3}
36: {1,1,2,2}
42: {1,2,4}
48: {1,1,1,1,2}
54: {1,2,2,2}
60: {1,1,2,3}
63: {2,2,4}
65: {3,6}
66: {1,2,5}
70: {1,3,4}
72: {1,1,1,2,2}
78: {1,2,6}
84: {1,1,2,4}
90: {1,2,2,3}
96: {1,1,1,1,1,2}
For all differences of pairs the complement is
A364347, counted by
A364345.
Subsets of {1..n} of this type are counted by
A364466, complement
A364463.
A325325 counts partitions with distinct first differences.
Cf.
A002865,
A025065,
A093971,
A108917,
A196723,
A229816,
A236912,
A237113,
A237667,
A320347,
A326083.
-
prix[n_]:=If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]];
Select[Range[100],Intersection[prix[#],Differences[prix[#]]]!={}&]
A364673
Number of (necessarily strict) integer partitions of n containing all of their own first differences.
Original entry on oeis.org
1, 1, 1, 2, 1, 1, 3, 2, 1, 2, 2, 2, 5, 2, 2, 4, 2, 3, 6, 4, 4, 8, 4, 4, 10, 8, 7, 8, 13, 9, 15, 12, 13, 17, 20, 15, 31, 24, 27, 32, 33, 32, 50, 42, 45, 53, 61, 61, 85, 76, 86, 101, 108, 118, 137, 141, 147, 179, 184, 196, 222, 244, 257, 295, 324, 348, 380, 433
Offset: 0
The partition y = (12,6,3,2,1) has differences (6,3,1,1), and {1,3,6} is a subset of {1,2,3,6,12}, so y is counted under a(24).
The a(n) partitions for n = 1, 3, 6, 12, 15, 18, 21:
(1) (3) (6) (12) (15) (18) (21)
(2,1) (4,2) (8,4) (10,5) (12,6) (14,7)
(3,2,1) (6,4,2) (8,4,2,1) (9,6,3) (12,6,3)
(5,4,2,1) (5,4,3,2,1) (6,5,4,2,1) (8,6,4,2,1)
(6,3,2,1) (7,5,3,2,1) (9,5,4,2,1)
(8,4,3,2,1) (9,6,3,2,1)
(10,5,3,2,1)
(6,5,4,3,2,1)
Containing all differences:
A007862.
For submultisets instead of subsets we have
A364675.
A236912 counts sum-free partitions w/o re-used parts, complement
A237113.
A325325 counts partitions with distinct first differences.
Cf.
A002865,
A025065,
A196723,
A229816,
A237667,
A320347,
A363225,
A364272,
A364345,
A364463,
A364537,
A370386.
-
Table[Length[Select[IntegerPartitions[n],UnsameQ@@#&&SubsetQ[#,-Differences[#]]&]],{n,0,30}]
-
from collections import Counter
def A364673_list(maxn):
count = Counter()
for i in range(maxn//3):
A,f,i = [[(i+1, )]],0,0
while f == 0:
A.append([])
for j in A[i]:
for k in j:
x = j + (j[-1] + k, )
y = sum(x)
if y <= maxn:
A[i+1].append(x)
count.update({y})
if len(A[i+1]) < 1: f += 1
i += 1
return [count[z]+1 for z in range(maxn+1)] # John Tyler Rascoe, Mar 09 2024
A365006
Number of strict integer partitions of n such that no part can be written as a (strictly) positive linear combination of the others.
Original entry on oeis.org
1, 1, 1, 1, 1, 2, 1, 3, 2, 4, 4, 8, 4, 11, 9, 16, 14, 25, 20, 37, 31, 49, 47, 73, 64, 101, 96, 135, 133, 190, 181, 256, 253, 336, 342, 453, 452, 596, 609, 771, 803, 1014, 1041, 1309, 1362, 1674, 1760, 2151, 2249, 2736, 2884, 3449, 3661, 4366, 4615, 5486, 5825
Offset: 0
The a(8) = 2 through a(13) = 11 partitions:
(8) (9) (10) (11) (12) (13)
(5,3) (5,4) (6,4) (6,5) (7,5) (7,6)
(7,2) (7,3) (7,4) (5,4,3) (8,5)
(4,3,2) (4,3,2,1) (8,3) (5,4,2,1) (9,4)
(9,2) (10,3)
(5,4,2) (11,2)
(6,3,2) (6,4,3)
(5,3,2,1) (6,5,2)
(7,4,2)
(5,4,3,1)
(6,4,2,1)
The nonnegative version for subsets appears to be
A124506.
For subsets instead of partitions we have
A365044, complement
A365043.
A364912 counts linear combinations of partitions of k.
-
combp[n_,y_]:=With[{s=Table[{k,i},{k,y},{i,1,Floor[n/k]}]},Select[Tuples[s],Total[Times@@@#]==n&]];
Table[Length[Select[IntegerPartitions[n],UnsameQ@@#&&And@@Table[combp[#[[k]],Delete[#,k]]=={},{k,Length[#]}]&]],{n,0,30}]
-
from sympy.utilities.iterables import partitions
def A365006(n):
if n <= 1: return 1
alist = [set(tuple(sorted(set(p))) for p in partitions(i)) for i in range(n)]
c = 1
for p in partitions(n,k=n-1):
if max(p.values()) == 1:
s = set(p)
for q in s:
if tuple(sorted(s-{q})) in alist[q]:
break
else:
c += 1
return c # Chai Wah Wu, Sep 20 2023
A365044
Number of subsets of {1..n} whose greatest element cannot be written as a (strictly) positive linear combination of the others.
Original entry on oeis.org
1, 2, 3, 5, 9, 20, 43, 96, 207, 442, 925, 1913, 3911, 7947, 16061, 32350, 64995, 130384, 261271, 523194, 1047208, 2095459, 4192212, 8386044, 16774078, 33550622, 67104244, 134212163, 268428760, 536862900, 1073732255, 2147472267, 4294953778, 8589918612, 17179850312
Offset: 0
The subset S = {3,5,6,8} has 6 = 2*3 + 0*5 + 0*8 and 8 = 1*3 + 1*5 + 0*6 but neither of these is strictly positive, so S is counted under a(8).
The a(0) = 1 through a(5) = 20 subsets:
{} {} {} {} {} {}
{1} {1} {1} {1} {1}
{2} {2} {2} {2}
{3} {3} {3}
{2,3} {4} {4}
{2,3} {5}
{3,4} {2,3}
{2,3,4} {2,5}
{1,2,3,4} {3,4}
{3,5}
{4,5}
{2,3,4}
{2,4,5}
{3,4,5}
{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}
A085489 and
A364755 count subsets w/o the sum of two distinct elements.
A088809 and
A364756 count subsets with the sum of two distinct elements.
A364350 counts combination-free strict partitions, complement
A364839.
A364913 counts combination-full partitions.
Cf.
A006951,
A237113,
A237668,
A308546,
A324736,
A326020,
A326080,
A364272,
A364349,
A364534,
A365069.
-
combp[n_,y_]:=With[{s=Table[{k,i},{k,y},{i,1,Floor[n/k]}]},Select[Tuples[s],Total[Times@@@#]==n&]];
Table[Length[Select[Subsets[Range[n]],And@@Table[combp[Last[#],Union[Most[#]]]=={},{k,Length[#]}]&]],{n,0,10}]
-
from itertools import combinations
from sympy.utilities.iterables import partitions
def A365044(n):
mlist = tuple({tuple(sorted(p.keys())) for p in partitions(m,k=m-1)} for m in range(1,n+1))
return n+1+sum(1 for k in range(2,n+1) for w in combinations(range(1,n+1),k) if w[:-1] not in mlist[w[-1]-1]) # Chai Wah Wu, Nov 20 2023
A365042
Number of subsets of {1..n} containing n such that some element can be written as a positive linear combination of the others.
Original entry on oeis.org
0, 0, 1, 2, 4, 5, 9, 11, 17, 21, 29, 36, 50, 60, 78, 95, 123, 147, 185, 221, 274, 325, 399, 472, 574, 672, 810, 945, 1131, 1316, 1557, 1812, 2137, 2462, 2892, 3322, 3881, 4460, 5176, 5916, 6846, 7817, 8993, 10250, 11765, 13333, 15280, 17308, 19731, 22306
Offset: 0
The subset {3,4,10} has 10 = 2*3 + 1*4 so is counted under a(10).
The a(0) = 0 through a(7) = 11 subsets:
. . {1,2} {1,3} {1,4} {1,5} {1,6} {1,7}
{1,2,3} {2,4} {1,2,5} {2,6} {1,2,7}
{1,2,4} {1,3,5} {3,6} {1,3,7}
{1,3,4} {1,4,5} {1,2,6} {1,4,7}
{2,3,5} {1,3,6} {1,5,7}
{1,4,6} {1,6,7}
{1,5,6} {2,3,7}
{2,4,6} {2,5,7}
{1,2,3,6} {3,4,7}
{1,2,3,7}
{1,2,4,7}
Without re-usable parts we have
A365069, first differences of
A364534.
A085489 and
A364755 count subsets with no sum of two distinct elements.
A088314 counts sets that can be linearly combined to obtain n.
A088809 and
A364756 count subsets with some sum of two distinct elements.
A364350 counts combination-free strict partitions, complement
A364839.
A364913 counts combination-full partitions.
-
combp[n_,y_]:=With[{s=Table[{k,i},{k,y},{i,1,Floor[n/k]}]},Select[Tuples[s],Total[Times@@@#]==n&]];
Table[Length[Select[Subsets[Range[n]],MemberQ[#,n]&&Or@@Table[combp[#[[k]],Union[Delete[#,k]]]!={},{k,Length[#]}]&]],{n,0,10}]
A365070
Number of subsets of {1..n} containing n and some element equal to the sum of two other (possibly equal) elements.
Original entry on oeis.org
0, 0, 1, 1, 5, 9, 24, 46, 109, 209, 469, 922, 1932, 3858, 7952, 15831, 32214, 64351, 129813, 259566, 521681, 1042703, 2091626, 4182470, 8376007, 16752524, 33530042, 67055129, 134165194, 268328011, 536763582, 1073523097, 2147268041, 4294505929, 8589506814, 17178978145
Offset: 0
The subset {1,3} has no element equal to the sum of two others, so is not counted under a(3).
The subset {3,4,5} has no element equal to the sum of two others, so is not counted under a(5).
The subset {1,3,4} has 4 = 1 + 3, so is counted under a(4).
The subset {2,4,5} has 4 = 2 + 2, so is counted under a(5).
The a(0) = 0 through a(5) = 9 subsets:
. . {1,2} {1,2,3} {2,4} {1,2,5}
{1,2,4} {1,4,5}
{1,3,4} {2,3,5}
{2,3,4} {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 w/o re-usable parts is
A085489, first differences of
A364755.
The case without re-usable parts is
A364756, firsts differences of
A088809.
A364350 counts combination-free strict partitions, complement
A364839.
A364913 counts combination-full partitions.
A365006 counts no positive combination-full strict ptns.
-
Table[Length[Select[Subsets[Range[n]], MemberQ[#,n]&&Intersection[#,Total /@ Tuples[#,2]]!={}&]], {n,0,10}]
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