A196087
Sum of all parts minus the total numbers of parts of all partitions of n.
Original entry on oeis.org
0, 1, 3, 8, 15, 31, 51, 90, 142, 228, 341, 525, 757, 1110, 1572, 2233, 3084, 4286, 5812, 7910, 10580, 14145, 18659, 24626, 32099, 41814, 53976, 69559, 88932, 113557, 143967, 182241, 229353, 288078, 360029, 449158, 557757, 691369, 853628, 1051974
Offset: 1
For n = 4 the five partitions of 4 are: 4, 3+1, 2+2, 2+1+1, 1+1+1+1. The sum of all parts is 4+3+1+2+2+2+1+1+1+1+1+1 = 20. The sum of all parts is also the product n*p(n) = 4*5 = 20, where p(n) = A000041(n) is the number of partitions of n. On the other hand the number of parts in all partitions of 4 is equal to 12, so a(4) = 20-12 = 8.
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b:= proc(n, i) option remember; local f, g;
if n=0 then [1, 0]
elif i<1 then [0, 0]
elif i>n then b(n, i-1)
else f:= b(n, i-1); g:= b(n-i, i);
[f[1]+g[1], f[2]+g[2] +g[1]*(i-1)]
fi
end:
a:= n-> b(n, n)[2]:
seq(a(n), n=1..50); # Alois P. Heinz, Feb 20 2012
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b[n_, i_] := b[n, i] = Module[{f, g}, Which[n==0, {1, 0}, i<1, {0, 0}, i>n, b[n, i-1], True, f = b[n, i-1]; g = b[n-i, i]; {f[[1]] + g[[1]], f[[2]] + g[[2]] + g[[1]]*(i-1)}]]; a[n_] := b[n, n][[2]]; Table[a[n], {n, 1, 50}] (* Jean-François Alcover, Oct 22 2015, after Alois P. Heinz *)
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a(n) = n*numbpart(n) - sum(m=1, n, numdiv(m)*numbpart(n-m)); \\ Michel Marcus, Oct 22 2015
A207034
Sum of all parts minus the number of parts of the n-th partition in the list of colexicographically ordered partitions of j, if 1<=n<=A000041(j).
Original entry on oeis.org
0, 1, 2, 2, 3, 3, 4, 3, 4, 4, 5, 4, 5, 5, 6, 4, 5, 5, 6, 6, 6, 7, 5, 6, 6, 7, 6, 7, 7, 8, 5, 6, 6, 7, 7, 7, 8, 7, 8, 8, 8, 9, 6, 7, 7, 8, 7, 8, 8, 9, 8, 8, 9, 9, 9, 10, 6, 7, 7, 8, 8, 8, 9, 8, 9, 9, 9, 10, 8, 9, 9, 10, 9, 10, 10, 10, 11, 7, 8, 8, 9, 8, 9
Offset: 1
Illustration of initial terms, n = 1..15. Consider the last 15 rows of the tail of the last section of the set of partitions in colexicographic order of any integer >= 8. The tail contains at least A000041(8-1) = 15 parts of size 1. a(n) is also the number of dots in the n-th row of the diagram.
----------------------------------
n Tail a(n)
----------------------------------
15 1 . . . . . . 6
14 1 . . . . . 5
13 1 . . . . . 5
12 1 . . . . 4
11 1 . . . . . 5
10 1 . . . . 4
9 1 . . . . 4
8 1 . . . 3
7 1 . . . . 4
6 1 . . . 3
5 1 . . . 3
4 1 . . 2
3 1 . . 2
2 1 . 1
1 1 0
----------------------------------
Written as a triangle:
0;
1;
2;
2,3;
3,4;
3,4,4,5;
4,5,5,6;
4,5,5,6,6,6,7;
5,6,6,7,6,7,7,8;
5,6,6,7,7,7,8,7,8,8,8,9;
6,7,7,8,7,8,8,9,8,8,9,9,9,10;
6,7,7,8,8,8,9,8,9,9,9,10,8,9,9,10,9,10,10,10,11;
...
Consider a matrix [j X A000041(j)] in which the rows represent the partitions of j in colexicographic order (see A211992). Every part of every partition is located in a cell of the matrix. We can see that a(n) is the number of empty cells in row n for any integer j, if A000041(j) >= n. The number of empty cells in row n equals the sum of all parts minus the number of parts in the n-th partition of j.
Illustration of initial terms. The smallest part of every partition is located in the last column of the matrix.
---------------------------------------------------------
. j: 1 2 3 4 5 6
n a(n)
---------------------------------------------------------
1 0 | 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
2 1 | . 2 . 2 1 . 2 1 1 . 2 1 1 1 . 2 1 1 1 1
3 2 | . . 3 . . 3 1 . . 3 1 1 . . 3 1 1 1
4 2 | . . 2 2 . . 2 2 1 . . 2 2 1 1
5 3 | . . . 4 . . . 4 1 . . . 4 1 1
6 3 | . . . 3 2 . . . 3 2 1
7 4 | . . . . 5 . . . . 5 1
8 3 | . . . 2 2 2
9 4 | . . . . 4 2
10 4 | . . . . 3 3
11 5 | . . . . . 6
...
Illustration of initial terms. In this case the largest part of every partition is located in the first column of the matrix.
---------------------------------------------------------
. j: 1 2 3 4 5 6
n a(n)
---------------------------------------------------------
1 0 | 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1
2 1 | 2 . 2 1 . 2 1 1 . 2 1 1 1 . 2 1 1 1 1 .
3 2 | 3 . . 3 1 . . 3 1 1 . . 3 1 1 1 . .
4 2 | 2 2 . . 2 2 1 . . 2 2 1 1 . .
5 3 | 4 . . . 4 1 . . . 4 1 1 . . .
6 3 | 3 2 . . . 3 2 1 . . .
7 4 | 5 . . . . 5 1 . . . .
8 3 | 2 2 2 . . .
9 4 | 4 2 . . . .
10 4 | 3 3 . . . .
11 5 | 6 . . . . .
...
Cf.
A135010,
A138121,
A141285,
A182703,
A194548,
A196087,
A207031,
A207032,
A207035,
A211992,
A228716,
A230440.
Original entry on oeis.org
0, 1, 3, 5, 8, 11, 15, 18, 22, 26, 31, 35, 40, 45, 51, 55, 60, 65, 71, 77, 83, 90, 95, 101, 107, 114, 120, 127, 134, 142, 147, 153, 159, 166, 173, 180, 188, 195, 203, 211, 219, 228, 234, 241, 248, 256, 263, 271, 279, 288, 296, 304, 313, 322, 331, 341
Offset: 1
Written as a triangle:
0;
1;
3;
5,8;
11,15;
18,22,26,31;
35,40,45,51;
55,60,65,71,77,83,90;
95,101,107,114,120,127,134,142;
147,153,159,166,173,180,188,195,203,211,219,228;
234,241,248,256,263,271,279,288,296,304,313,322,331,341;
A182276
Sum of all parts minus the total number of parts of the shell model of partitions with n regions.
Original entry on oeis.org
0, 1, 3, 4, 8, 10, 15, 16, 20, 22, 31, 33, 38, 41, 51, 52, 56, 58, 67, 71, 74, 90, 92, 97, 100, 110, 112, 119, 123, 142, 143, 147, 149, 158, 162, 165, 181, 184, 192, 197, 201, 228, 230, 235, 238, 248, 250, 257, 261, 280, 284, 287, 299, 305, 310, 341
Offset: 1
Written has a triangle:
0,
1,
3,
4, 8;
10, 15;
16, 20, 22, 31;
33, 38, 41, 51;
52, 56, 58, 67, 71, 74, 90;
92, 97,100,110,112,119,123,142;
143,147,149,158,162,165,181,184,192,197,201,228;
230,235,238,248,250,257,261,280,284,287,299,305,310,341;
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lex[n_]:=DeleteCases[Sort@PadRight[Reverse /@ IntegerPartitions@n], x_ /; x==0,2];
reg = {}; l = {};
For[j = 1, j <= 56, j++,
mx = Max@lex[j][[j]]; AppendTo[l, mx];
For[i = j, i > 0, i--, If[l[[i]] > mx, Break[]]];
t = Take[Reverse[First /@ lex[mx]], j - i];
AppendTo[reg, Total@t - Length@t]
];
Accumulate@reg (* Robert Price, Jul 25 2020 *)
A210946
Triangle read by rows: T(n,k) = sum of parts in the k-th column of the mirror of the last section of the set of partitions of n with its parts aligned to the right margin.
Original entry on oeis.org
1, 3, 5, 9, 2, 12, 3, 20, 9, 2, 25, 11, 3, 38, 22, 9, 2, 49, 28, 14, 3, 69, 44, 26, 9, 2, 87, 55, 37, 14, 3, 123, 83, 62, 29, 9, 2, 152
Offset: 1
For n = 7 the illustration shows two arrangements of the last section of the set of partitions of 7:
.
. (7) (7)
. (4+3) (3+4)
. (5+2) (2+5)
. (3+2+2) (2+2+3)
. (1) (1)
. (1) (1)
. (1) (1)
. (1) (1)
. (1) (1)
. (1) (1)
. (1) (1)
. (1) (1)
. (1) (1)
. (1) (1)
. (1) (1)
. ---------
. 25,11,3
.
The left hand picture shows the last section of 7 with its parts aligned to the right margin. In the right hand picture (the mirror) we can see that the sum of all parts of the columns 1..3 are 25, 11, 3 therefore row 7 lists 25, 11, 3.
Written as a triangle begins:
1;
3;
5;
9, 2;
12, 3;
20, 9, 2;
25, 11, 3;
38, 22, 9, 2;
49, 28, 14, 3;
69, 44, 26, 9, 2;
87, 55, 37, 14, 3,
123, 83, 62, 29, 9, 2;
Cf.
A135010,
A138121,
A182703,
A194714,
A196807,
A206437,
A207031,
A207034,
A207035,
A210945,
A210952,
A210953.
Showing 1-5 of 5 results.
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