A207383
Triangle read by rows: T(n,k) is the sum of parts of size k in the last section of the set of partitions of n.
Original entry on oeis.org
1, 1, 2, 2, 0, 3, 3, 4, 0, 4, 5, 2, 3, 0, 5, 7, 8, 6, 4, 0, 6, 11, 6, 6, 4, 5, 0, 7, 15, 16, 9, 12, 5, 6, 0, 8, 22, 14, 18, 8, 10, 6, 7, 0, 9, 30, 30, 18, 20, 15, 12, 7, 8, 0, 10, 42, 30, 30, 20, 20, 12, 14, 8, 9, 0, 11, 56, 54, 42, 40, 25, 30, 14, 16, 9, 10, 0, 12
Offset: 1
Triangle begins:
1;
1, 2;
2, 0, 3;
3, 4, 0, 4;
5, 2, 3, 0, 5;
7, 8, 6, 4, 0, 6;
11, 6, 6, 4, 5, 0, 7;
15, 16, 9, 12, 5, 6, 0, 8;
22, 14, 18, 8, 10, 6, 7, 0, 9;
30, 30, 18, 20, 15, 12, 7, 8, 0, 10;
42, 30, 30, 20, 20, 12, 14, 8, 9, 0, 11;
56, 54, 42, 40, 25, 30, 14, 16, 9, 10, 0, 12;
...
From _Omar E. Pol_, Nov 28 2020: (Start)
Illustration of three arrangements of the last section of the set of partitions of 7, or more generally the 7th section of the set of partitions of any integer >= 7:
. _ _ _ _ _ _ _
. (7) (7) |_ _ _ _ |
. (4+3) (4+3) |_ _ _ _|_ |
. (5+2) (5+2) |_ _ _ | |
. (3+2+2) (3+2+2) |_ _ _|_ _|_ |
. (1) (1) | |
. (1) (1) | |
. (1) (1) | |
. (1) (1) | |
. (1) (1) | |
. (1) (1) | |
. (1) (1) | |
. (1) (1) | |
. (1) (1) | |
. (1) (1) | |
. (1) (1) |_|
. ----------------
. 19,8,5,3,2,1,1 --> Row 7 of triangle A207031
. |/|/|/|/|/|/|
. 11,3,2,1,1,0,1 --> Row 7 of triangle A182703
. * * * * * * *
. 1,2,3,4,5,6,7 --> Row 7 of triangle A002260
. = = = = = = =
. 11,6,6,4,5,0,7 --> Row 7 of this triangle
.
Note that the "head" of the last section is formed by the partitions of 7 that do not contain 1 as a part. The "tail" is formed by A000041(7-1) parts of size 1. The number of rows (or zones) is A000041(7) = 15. The last section of the set of partitions of 7 contains eleven 1's, three 2's, two 3's, one 4, one 5, there are no 6's and it contains one 7. So the 7th row of triangle is [11, 6, 6, 4, 5, 0, 7]. (End)
A182982
Triangle read by rows: row n lists the parts of the n-th shell of the table A182742.
Original entry on oeis.org
2, 2, 4, 2, 2, 3, 3, 6, 2, 2, 2, 2, 3, 5, 4, 4, 8, 2, 2, 2, 2, 2, 2, 2, 3, 3, 4, 3, 7, 4, 6, 5, 5, 10, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 6, 3, 4, 5, 3, 9, 4, 4, 4, 4, 8, 5, 7, 6, 6, 12, 2, 2, 2, 2, 2, 2, 2, 2, 2
Offset: 1
Triangle begins:
2,
2, 4,
2, 2, 3, 3, 6,
2, 2, 2, 2, 3, 5, 4, 4, 8,
2, 2, 2, 2, 2, 2, 2, 3, 3, 4, 3, 7, 4, 6, 5, 5, 10
A182983
Triangle read by rows: row n lists the parts of the n-th shell of the table A182743.
Original entry on oeis.org
3, 2, 5, 2, 2, 3, 4, 7, 2, 2, 2, 2, 3, 3, 3, 3, 6, 4, 5, 9, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 5, 3, 4, 4, 3, 8, 4, 7, 5, 6, 11, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 4, 3, 3, 7, 3, 4, 6, 3, 5, 5, 3, 10, 4, 4, 5, 4, 9, 5, 8, 6, 7, 13, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2
Offset: 1
Triangle begins:
3,
2, 5,
2, 2, 3, 4, 7,
2, 2, 2, 2, 3, 3, 3, 3, 6, 4, 5, 9
A183152
Irregular triangle read by rows in which row n lists the emergent parts of all partitions of n, or 0 if such parts do not exist.
Original entry on oeis.org
0, 0, 0, 0, 2, 3, 2, 4, 2, 3, 3, 5, 2, 4, 2, 4, 2, 3, 6, 3, 2, 2, 5, 4, 3, 5, 2, 4, 7, 3, 2, 2, 3, 6, 3, 5, 2, 4, 2, 3, 6, 3, 2, 2, 5, 4, 8, 4, 3, 2, 2, 2, 2, 4, 7, 3, 6, 5, 3, 5, 2, 4, 7, 3, 2, 2, 3, 6, 3, 5, 9, 4, 3, 3, 2, 2, 2, 2, 5, 4, 8, 4, 3, 7, 6
Offset: 0
If written as a triangle:
0,
0,
0,
0,
2,
3,
2,4,2,3,
3,5,2,4,
2,4,2,3,6,3,2,2,5,4,
3,5,2,4,7,3,2,2,3,6,3,5,
2,4,2,3,6,3,2,2,5,4,8,4,3,2,2,2,2,4,7,3,6,5,
3,5,2,4,7,3,2,2,3,6,3,5,9,4,3,3,2,2,2,2,5,4,8,4,3,7,6
A182746
Bisection (even part) of number of partitions that do not contain 1 as a part A002865.
Original entry on oeis.org
1, 1, 2, 4, 7, 12, 21, 34, 55, 88, 137, 210, 320, 478, 708, 1039, 1507, 2167, 3094, 4378, 6153, 8591, 11914, 16424, 22519, 30701, 41646, 56224, 75547, 101066, 134647, 178651, 236131, 310962, 408046, 533623, 695578, 903811, 1170827, 1512301, 1947826, 2501928
Offset: 0
- Alois P. Heinz, Table of n, a(n) for n = 0..1000
- Marco Baggio, Vasilis Niarchos, Kyriakos Papadodimas, and Gideon Vos, Large-N correlation functions in N = 2 superconformal QCD, arXiv preprint arXiv:1610.07612 [hep-th], 2016.
- K. Blum, Bounds on the Number of Graphical Partitions, arXiv:2103.03196 [math.CO], 2021. See Table on p. 7.
-
b:= proc(n, i) option remember;
if n<0 then 0
elif n=0 then 1
elif i<2 then 0
else b(n, i-1) +b(n-i, i)
fi
end:
a:= n-> b(2*n, 2*n):
seq(a(n), n=0..40); # Alois P. Heinz, Dec 01 2010
-
Table[Count[IntegerPartitions[2 n -1], p_ /; MemberQ[p, Length[p]]], {n, 20}] (* Clark Kimberling, Mar 02 2014 *)
b[n_, i_] := b[n, i] = Which[n<0, 0, n==0, 1, i<2, 0, True, b[n, i-1] + b[n-i, i]]; a[n_] := b[2*n, 2*n]; Table[a[n], {n, 0, 40}] (* Jean-François Alcover, Sep 21 2015, after Alois P. Heinz *)
a[n_] := PartitionsP[2*n] - PartitionsP[2*n - 1]; Table[a[n], {n, 0, 40}] (* George Beck, Jun 05 2017 *)
-
a(n)=numbpart(2*n)-numbpart(2*n-1) \\ Charles R Greathouse IV, Jun 06 2017
A207779
Largest part plus the number of parts of the n-th region of the section model of partitions.
Original entry on oeis.org
2, 4, 6, 3, 9, 4, 12, 3, 6, 4, 17, 4, 7, 5, 22, 3, 6, 4, 10, 6, 5, 30, 4, 7, 5, 11, 4, 8, 6, 39, 3, 6, 4, 10, 6, 5, 15, 5, 9, 7, 6, 52, 4, 7, 5, 11, 4, 8, 6, 17, 6, 5, 11, 8, 7, 67, 3, 6, 4, 10, 6, 5, 15, 5, 9, 7, 6, 22, 4, 8, 6, 13, 5, 10, 8
Offset: 1
Written as a triangle begins:
2;
4;
6;
3, 9;
4, 12;
3, 6, 4, 17;
4, 7, 5, 22;
3, 6, 4, 10, 6, 5, 30;
4, 7, 5, 11, 4, 8, 6, 39;
3, 6, 4, 10, 6, 5, 15, 5, 9, 7, 6, 52;
Cf.
A002865,
A135010,
A182699,
A182709,
A183152,
A194436,
A194437,
A194438,
A194439,
A194447,
A206437.
A058399
Triangle of partial row sums of partition triangle A008284.
Original entry on oeis.org
1, 2, 1, 3, 2, 1, 5, 4, 2, 1, 7, 6, 4, 2, 1, 11, 10, 7, 4, 2, 1, 15, 14, 11, 7, 4, 2, 1, 22, 21, 17, 12, 7, 4, 2, 1, 30, 29, 25, 18, 12, 7, 4, 2, 1, 42, 41, 36, 28, 19, 12, 7, 4, 2, 1, 56, 55, 50, 40, 29, 19, 12, 7, 4, 2, 1, 77, 76, 70, 58, 43, 30, 19, 12, 7, 4, 2, 1, 101, 100, 94, 80, 62
Offset: 1
From _Omar E. Pol_, Mar 10 2012: (Start)
Triangle begins:
1;
2, 1;
3, 2, 1;
5, 4, 2, 1;
7, 6, 4, 2, 1;
11, 10, 7, 4, 2, 1;
15, 14, 11, 7, 4, 2, 1;
22, 21, 17, 12, 7, 4, 2, 1;
30, 29, 25, 18, 12, 7, 4, 2, 1;
42, 41, 36, 28, 19, 12, 7, 4, 2, 1;
56, 55, 50, 40, 29, 19, 12, 7, 4, 2, 1;
77, 76, 70, 58, 43, 30, 19, 12, 7, 4, 2, 1;
(End)
-
b:= proc(n, k) option remember;
`if`(n=0, 1, `if`(k<1, 0, add(b(n-j*k, k-1), j=0..n/k)))
end:
T:= (n, m)-> b(n,n) -b(n,m-1):
seq (seq (T(n, m), m=1..n), n=1..15); # Alois P. Heinz, Apr 20 2012
-
t[n_, m_] := Sum[ IntegerPartitions[n, {k}] // Length, {k, m, n}]; Table[t[n, m], {n, 1, 13}, {m, 1, n}] // Flatten (* Jean-François Alcover, Jun 21 2013 *)
A182747
Bisection (odd part) of number of partitions that do not contain 1 as a part A002865.
Original entry on oeis.org
0, 1, 2, 4, 8, 14, 24, 41, 66, 105, 165, 253, 383, 574, 847, 1238, 1794, 2573, 3660, 5170, 7245, 10087, 13959, 19196, 26252, 35717, 48342, 65121, 87331, 116600, 155038, 205343, 270928, 356169, 466610, 609237, 792906, 1028764, 1330772, 1716486, 2207851
Offset: 0
-
b:= proc(n,i) option remember;
if n<0 then 0
elif n=0 then 1
elif i<2 then 0
else b(n, i-1) +b(n-i, i)
fi
end:
a:= n-> b(2*n+1, 2*n+1):
seq(a(n), n=0..40); # Alois P. Heinz, Dec 01 2010
-
f[n_] := Table[PartitionsP[2 k + 1] - PartitionsP[2 k], {k, 0, n}] (* George Beck, Aug 14 2011 *)
(* also *)
Table[Count[IntegerPartitions[2 n], p_ /; MemberQ[p, Length[p]]], {n, 20}] (* Clark Kimberling, Mar 02 2014 *)
b[n_, i_] := b[n, i] = Which[n<0, 0, n == 0, 1, i<2, 0, True, b[n, i-1] + b[n-i, i]]; a[n_] := b[2*n+1, 2*n+1]; Table[a[n], {n, 0, 40}] (* Jean-François Alcover, Aug 29 2016, after Alois P. Heinz *)
A195820
Total number of smallest parts in all partitions of n that do not contain 1 as a part.
Original entry on oeis.org
0, 1, 1, 3, 2, 7, 5, 12, 13, 22, 22, 43, 43, 67, 81, 117, 133, 195, 223, 312, 373, 492, 584, 782, 925, 1190, 1433, 1820, 2170, 2748, 3268, 4075, 4872, 5997, 7150, 8781, 10420, 12669, 15055, 18198, 21535, 25925, 30602, 36624, 43201, 51428, 60478, 71802, 84215
Offset: 1
For n = 8 the seven partitions of 8 that do not contain 1 as a part are:
. (8)
. (4) + (4)
. 5 + (3)
. 6 + (2)
. 3 + 3 + (2)
. 4 + (2) + (2)
. (2) + (2) + (2) + (2)
Note that in every partition the smallest parts are shown between parentheses. The total number of smallest parts is 1+2+1+1+1+2+4 = 12, so a(8) = 12.
- Alois P. Heinz, Table of n, a(n) for n = 1..1000
- G. E. Andrews, The number of smallest parts in the partitions of n
- A. Folsom and K. Ono, The spt-function of Andrews
- F. G. Garvan, Congruences for Andrews' spt-function modulo 32760 and extension of Atkin's Hecke-type partition congruences, arXiv:1011.1957 [math.NT], 2020.
- F. G. Garvan, Congruences for Andrews' spt-function modulo powers of 5, 7 and 13, arXiv:1011.1955 [math.NT], 2010.
- K. Ono, Congruences for the Andrews spt-function
- Wikipedia, Spt function
-
b:= proc(n, i) option remember;
`if`(n=0 or i<2, 0, b(n, i-1)+
add(`if`(n=i*j, j, b(n-i*j, i-1)), j=1..n/i))
end:
a:= n-> b(n, n):
seq(a(n), n=1..60); # Alois P. Heinz, Apr 09 2012
-
Table[s = Select[IntegerPartitions[n], ! MemberQ[#, 1] &]; Plus @@ Table[Count[x, Min[x]], {x, s}], {n, 50}] (* T. D. Noe, Oct 19 2011 *)
b[n_, i_] := b[n, i] = If[n==0 || i<2, 0, b[n, i-1] + Sum[If[n== i*j, j, b[n-i*j, i-1]], {j, 1, n/i}]]; a[n_] := b[n, n]; Table[a[n], {n, 1, 60}] (* Jean-François Alcover, Oct 12 2015, after Alois P. Heinz *)
-
def A195820(n):
return sum(list(p).count(min(p)) for p in Partitions(n,min_part=2))
# D. S. McNeil, Oct 19 2011
A207032
Triangle read by rows: T(n,k) = number of odd/even parts >= k in the last section of the set of partitions of n, if k is odd/even.
Original entry on oeis.org
1, 1, 1, 3, 0, 1, 3, 3, 0, 1, 7, 1, 2, 0, 1, 9, 6, 2, 2, 0, 1, 15, 4, 4, 1, 2, 0, 1, 19, 13, 4, 5, 1, 2, 0, 1, 32, 10, 10, 3, 4, 1, 2, 0, 1, 40, 24, 10, 9, 4, 4, 1, 2, 0, 1, 60, 23, 18, 8, 8, 3, 4, 1, 2, 0, 1, 78, 46, 22, 19, 8, 9, 3, 4, 1, 2, 0, 1
Offset: 1
Triangle begins:
1;
1, 1;
3, 0, 1;
3, 3, 0, 1;
7, 1, 2, 0, 1;
9, 6, 2, 2, 0, 1;
15, 4, 4, 1, 2, 0, 1;
19, 13, 4, 5, 1, 2, 0, 1;
32, 10, 10, 3, 4, 1, 2, 0, 1;
40, 24, 10, 9, 4, 4, 1, 2, 0, 1;
60, 23, 18, 8, 8, 3, 4, 1, 2, 0, 1;
78, 46, 22, 19, 8, 9, 3, 4, 1, 2, 0, 1;
Cf.
A006128,
A066897,
A066898,
A135010,
A138121,
A138135,
A138137,
A141285,
A181187,
A182703,
A206563,
A207031.
Comments