A138121
Triangle read by rows in which row n lists the partitions of n that do not contain 1 as a part in juxtaposed reverse-lexicographical order followed by A000041(n-1) 1's.
Original entry on oeis.org
1, 2, 1, 3, 1, 1, 4, 2, 2, 1, 1, 1, 5, 3, 2, 1, 1, 1, 1, 1, 6, 3, 3, 4, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 7, 4, 3, 5, 2, 3, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 8, 4, 4, 5, 3, 6, 2, 3, 3, 2, 4, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 9, 5, 4, 6, 3, 3, 3, 3, 7, 2, 4, 3, 2, 5, 2, 2, 3, 2, 2
Offset: 1
Triangle begins:
[1];
[2],[1];
[3],[1],[1];
[4],[2,2],[1],[1],[1];
[5],[3,2],[1],[1],[1],[1],[1];
[6],[3,3],[4,2],[2,2,2],[1],[1],[1],[1],[1],[1],[1];
[7],[4,3],[5,2],[3,2,2],[1],[1],[1],[1],[1],[1],[1],[1],[1],[1],[1];
...
The illustration of the three views of the section model of partitions (version "tree" with seven sections) shows the connection between several sequences.
---------------------------------------------------------
Partitions A194805 Table 1.0
. of 7 p(n) A194551 A135010
---------------------------------------------------------
7 15 7 7 . . . . . .
4+3 4 4 . . . 3 . .
5+2 5 5 . . . . 2 .
3+2+2 3 3 . . 2 . 2 .
6+1 11 6 1 6 . . . . . 1
3+3+1 3 1 3 . . 3 . . 1
4+2+1 4 1 4 . . . 2 . 1
2+2+2+1 2 1 2 . 2 . 2 . 1
5+1+1 7 1 5 5 . . . . 1 1
3+2+1+1 1 3 3 . . 2 . 1 1
4+1+1+1 5 4 1 4 . . . 1 1 1
2+2+1+1+1 2 1 2 . 2 . 1 1 1
3+1+1+1+1 3 1 3 3 . . 1 1 1 1
2+1+1+1+1+1 2 2 1 2 . 1 1 1 1 1
1+1+1+1+1+1+1 1 1 1 1 1 1 1 1 1
. 1 ---------------
. *<------- A000041 -------> 1 1 2 3 5 7 11
. A182712 -------> 1 0 2 1 4 3
. A182713 -------> 1 0 1 2 2
. A182714 -------> 1 0 1 1
. 1 0 1
. A141285 A182703 1 0
. A182730 A182731 1
---------------------------------------------------------
. A138137 --> 1 2 3 6 9 15..
---------------------------------------------------------
. A182746 <--- 4 . 2 1 0 1 2 . 4 ---> A182747
---------------------------------------------------------
.
. A182732 <--- 6 3 4 2 1 3 5 4 7 ---> A182733
. . . . . 1 . . . .
. . . . 2 1 . . . .
. . 3 . . 1 2 . . .
. Table 2.0 . . 2 2 1 . . 3 . Table 2.1
. . . . . 1 2 2 . .
. 1 . . . .
.
. A182982 A182742 A194803 A182983 A182743
. A182992 A182994 A194804 A182993 A182995
---------------------------------------------------------
.
From _Omar E. Pol_, Sep 03 2013: (Start)
Illustration of initial terms (n = 1..6). The table shows the six sections of the set of partitions of 6. Note that before the dissection the set of partitions was in the ordering mentioned in A026792. More generally, the six sections of the set of partitions of 6 also can be interpreted as the first six sections of the set of partitions of any integer >= 6.
Illustration of initial terms:
---------------------------------------
n j Diagram Parts
---------------------------------------
. _
1 1 |_| 1;
. _ _
2 1 |_ | 2,
2 2 |_| . 1;
. _ _ _
3 1 |_ _ | 3,
3 2 | | . 1,
3 3 |_| . . 1;
. _ _ _ _
4 1 |_ _ | 4,
4 2 |_ _|_ | 2, 2,
4 3 | | . 1,
4 4 | | . . 1,
4 5 |_| . . . 1;
. _ _ _ _ _
5 1 |_ _ _ | 5,
5 2 |_ _ _|_ | 3, 2,
5 3 | | . 1,
5 4 | | . . 1,
5 5 | | . . 1,
5 6 | | . . . 1,
5 7 |_| . . . . 1;
. _ _ _ _ _ _
6 1 |_ _ _ | 6,
6 2 |_ _ _|_ | 3, 3,
6 3 |_ _ | | 4, 2,
6 4 |_ _|_ _|_ | 2, 2, 2,
6 5 | | . 1,
6 6 | | . . 1,
6 7 | | . . 1,
6 8 | | . . . 1,
6 9 | | . . . 1,
6 10 | | . . . . 1,
6 11 |_| . . . . . 1;
...
(End)
-
less[run1_, run2_] := (lg1 = run1 // Length; lg2 = run2 // Length; lg = Max[lg1, lg2]; r1 = If[lg1 == lg, run1, PadRight[run1, lg, 0]]; r2 = If[lg2 == lg, run2, PadRight[run2, lg, 0]]; Order[r1, r2] != -1); row[n_] := Join[Array[1 &, {PartitionsP[n - 1]}], Sort[Reverse /@ Select[IntegerPartitions[n], FreeQ[#, 1] &], less]] // Flatten // Reverse; Table[row[n], {n, 1, 9}] // Flatten (* Jean-François Alcover, Jan 15 2013 *)
Table[Reverse/@Reverse@DeleteCases[Sort@PadRight[Reverse/@Cases[IntegerPartitions[n], x_ /; Last[x]!=1]], x_ /; x==0, 2]~Join~ConstantArray[{1}, PartitionsP[n - 1]], {n, 1, 9}] // Flatten (* Robert Price, May 11 2020 *)
A240009
Number T(n,k) of partitions of n, where k is the difference between the number of odd parts and the number of even parts; triangle T(n,k), n>=0, -floor(n/2)+(n mod 2)<=k<=n, read by rows.
Original entry on oeis.org
1, 1, 1, 0, 0, 1, 1, 1, 0, 1, 1, 1, 0, 1, 1, 0, 1, 1, 2, 1, 1, 1, 0, 1, 1, 1, 1, 1, 2, 2, 1, 1, 0, 1, 1, 2, 3, 2, 2, 2, 1, 1, 0, 1, 1, 1, 2, 2, 2, 4, 3, 2, 2, 1, 1, 0, 1, 1, 2, 4, 5, 3, 4, 4, 2, 2, 1, 1, 0, 1, 1, 1, 2, 3, 3, 5, 7, 5, 4, 4, 2, 2, 1, 1, 0, 1, 1, 2, 4, 7, 7, 6, 8, 6, 4, 4, 2, 2, 1, 1, 0, 1
Offset: 0
T(5,-1) = 1: [2,2,1].
T(5,0) = 2: [4,1], [3,2].
T(5,1) = 1: [5].
T(5,2) = 1: [2,1,1,1].
T(5,3) = 1: [3,1,1].
T(5,5) = 1: [1,1,1,1,1].
Triangle T(n,k) begins:
: n\k : -5 -4 -3 -2 -1 0 1 2 3 4 5 6 7 8 9 10 ...
+-----+----------------------------------------------------
: 0 : 1;
: 1 : 1;
: 2 : 1, 0, 0, 1;
: 3 : 1, 1, 0, 1;
: 4 : 1, 1, 0, 1, 1, 0, 1;
: 5 : 1, 2, 1, 1, 1, 0, 1;
: 6 : 1, 1, 1, 1, 2, 2, 1, 1, 0, 1;
: 7 : 1, 2, 3, 2, 2, 2, 1, 1, 0, 1;
: 8 : 1, 1, 2, 2, 2, 4, 3, 2, 2, 1, 1, 0, 1;
: 9 : 1, 2, 4, 5, 3, 4, 4, 2, 2, 1, 1, 0, 1;
: 10 : 1, 1, 2, 3, 3, 5, 7, 5, 4, 4, 2, 2, 1, 1, 0, 1;
Columns k=(-1)-10 give:
A239832,
A045931,
A240010,
A240011,
A240012,
A240013,
A240014,
A240015,
A240016,
A240017,
A240018,
A240019.
Row lengths give
A016777(floor(n/2)).
Cf.
A240021 (the same for partitions into distinct parts),
A242618 (the same for parts counted without multiplicity).
-
b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0,
expand(b(n, i-1)+`if`(i>n, 0, b(n-i, i)*x^(2*irem(i, 2)-1)))))
end:
T:= n-> (p-> seq(coeff(p, x, i), i=ldegree(p)..degree(p)))(b(n$2)):
seq(T(n), n=0..14);
-
b[n_, i_] := b[n, i] = If[n == 0, 1, If[i<1, 0, b[n, i-1] + If[i>n, 0, b[n-i, i]*x^(2*Mod[i, 2]-1)]]]; T[n_] := (degree = Exponent[b[n, n], x]; ldegree = -Exponent[b[n, n] /. x -> 1/x, x]; Table[Coefficient[b[n, n], x, i], {i, ldegree, degree}]); Table[T[n], {n, 0, 14}] // Flatten (* Jean-François Alcover, Jan 06 2015, translated from Maple *)
-
N=20; q='q+O('q^N);
e(n) = if(n%2!=0, u, 1/u);
gf = 1 / prod(n=1,N, 1 - e(n)*q^n );
V = Vec( gf );
{ for (j=1, #V, \\ print triangle, including leading zeros
for (i=0, N-j, print1(" ")); \\ padding
for (i=-j+1, j-1, print1(polcoeff(V[j], i, u),", "));
print();
); }
/* Joerg Arndt, Mar 31 2014 */
A182742
Table of partitions that do not contain 1 as a part for even integers.
Original entry on oeis.org
2, 4, 2, 3, 2, 2, 6, 3, 2, 2, 5, 2, 2, 2, 2, 4, 3, 2, 2, 2, 2, 8, 4, 2, 2, 2, 2, 2, 4, 2, 2, 2, 2, 2, 2, 2, 7, 3, 2, 2, 2, 2, 2, 2, 2, 6, 3, 3, 2, 2, 2, 2, 2, 2, 2, 5, 4, 2, 2, 2, 2, 2, 2, 2, 2, 2, 10, 5, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 6, 3, 2, 2
Offset: 1
Array begins:
2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
4, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2,
3, 3, 2, 2, 2, 2, 2, 2, 2, 2,
6, 2, 2, 2, 2, 2, 2, 2, 2,
5, 3, 2, 2, 2, 2, 2, 2,
4, 4, 2, 2, 2, 2, 2,
8, 2, 2, 2, 2, 2,
4, 3, 3, 2, 2,
7, 3, 2, 2,
6, 4, 2,
5, 5,
10,
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 *)
A182732
The limit of row A182730(n,.) as n-> infinity.
Original entry on oeis.org
2, 4, 3, 6, 5, 4, 8, 4, 7, 6, 5, 10, 3, 6, 5, 9, 4, 8, 7, 6, 12, 5, 4, 8, 7, 6, 11, 6, 5, 10, 9, 8, 7, 14, 4, 7, 6, 5, 10, 5, 9, 8, 7, 13, 4, 8, 7, 6, 12, 6, 11, 10, 9, 8, 16, 3, 6, 5, 9, 4, 8, 7, 6, 12, 7, 6, 11, 5, 10, 9, 8, 15, 6, 5, 10, 9, 8, 7, 14, 8, 7, 13, 6, 12, 11, 10, 9, 18
Offset: 1
One together with where records occur give
A182746.
A182736
Sum of parts in all partitions of 2n that do not contain 1 as a part.
Original entry on oeis.org
0, 2, 8, 24, 56, 120, 252, 476, 880, 1584, 2740, 4620, 7680, 12428, 19824, 31170, 48224, 73678, 111384, 166364, 246120, 360822, 524216, 755504, 1080912, 1535050, 2165592, 3036096, 4230632, 5861828, 8078820, 11076362, 15112384, 20523492, 27747128
Offset: 0
-
b:= proc(n,i) option remember; local p,q;
if n<0 then [0,0]
elif n=0 then [1,0]
elif i<2 then [0,0]
else p, q:= b(n,i-1), b(n-i,i);
[p[1]+q[1], p[2]+q[2]+q[1]*i]
fi
end:
a:= n-> b(2*n,2*n)[2]:
seq(a(n), n=0..34); # Alois P. Heinz, Dec 03 2010
-
b[n_] := (PartitionsP[n] - PartitionsP[n-1])*n; a[n_] := b[2n]; Table[a[n], {n, 0, 34}] (* Jean-François Alcover, Oct 07 2015 *)
A194797
Imbalance of the sum of parts of all partitions of n.
Original entry on oeis.org
0, -2, 1, -7, 3, -21, 7, -49, 23, -97, 57, -195, 117, -359, 256, -624, 498, -1086, 909, -1831, 1634, -2986, 2833, -4847, 4728, -7700, 7798, -12026, 12537, -18633, 19745, -28479, 30723, -42955, 47100, -64284, 71136, -95228, 106402, -139718, 157327, -203495
Offset: 1
For n = 6 the illustration of the three views of the shell model with 6 shells shows an imbalance (see below):
------------------------------------------------------
Partitions Tree Table 1.0
of 6. A194805 A135010
------------------------------------------------------
6 6 6 . . . . .
3+3 3 3 . . 3 . .
4+2 4 4 . . . 2 .
2+2+2 2 2 . 2 . 2 .
5+1 1 5 5 . . . . 1
3+2+1 1 3 3 . . 2 . 1
4+1+1 4 1 4 . . . 1 1
2+2+1+1 2 1 2 . 2 . 1 1
3+1+1+1 1 3 3 . . 1 1 1
2+1+1+1+1 2 1 2 . 1 1 1 1
1+1+1+1+1+1 1 1 1 1 1 1 1
------------------------------------------------------
.
. 6 3 4 2 1 3 5
. Table 2.0 . . . . 1 . . Table 2.1
. A182982 . . . 2 1 . . A182983
. . 3 . . 1 2 .
. . . 2 2 1 . .
. . . . . 1
------------------------------------------------------
The sum of all parts > 1 on the left hand side is 34 and the sum of all parts > 1 on the right hand side is 13, so a(6) = -34 + 13 = -21. On the other hand for n = 6 the first n terms of A138880 are 0, 2, 3, 8, 10, 24 thus a(6) = 0-2+3-8+10-24 = -21.
Cf.
A000041,
A002865,
A135010,
A138121,
A138880,
A141285,
A182710,
A182742,
A182743,
A182746,
A182747,
A182982,
A182983,
A182994,
A182995,
A194796,
A194805.
-
with(combinat):
a:= proc(n) option remember;
n *(-1)^n *(numbpart(n-1)-numbpart(n)) +a(n-1)
end: a(0):=0:
seq(a(n), n=1..50); # Alois P. Heinz, Apr 04 2012
-
a[n_] := Sum[(-1)^(k-1)*k*(PartitionsP[k] - PartitionsP[k-1]), {k, 1, n}]; Array[a, 50] (* Jean-François Alcover, Dec 09 2016 *)
A182744
Second column of the table A182742.
Original entry on oeis.org
2, 2, 3, 2, 3, 4, 2, 3, 3, 4, 5, 2, 3, 3, 4, 3, 4, 4, 5, 6, 2, 3, 4, 3, 4, 5, 3, 4, 5, 4, 5, 6, 7, 2
Offset: 1
A182806
Number of partitions of 3n into parts >= 3.
Original entry on oeis.org
1, 2, 4, 9, 17, 33, 60, 110, 191, 331, 556, 927, 1510, 2438, 3872, 6095, 9465, 14578, 22210, 33581, 50305, 74831, 110441, 161955, 235858, 341474, 491365, 703263, 1001014, 1417812, 1998184, 2803342
Offset: 1
A182807
Number of partitions of 3n+1 into parts >= 3.
Original entry on oeis.org
1, 2, 5, 10, 21, 39, 73, 130, 230, 391, 660, 1087, 1775, 2842, 4510, 7056, 10945, 16779, 25519, 38438, 57480, 85241, 125577, 183669, 267016, 385714, 554102, 791483, 1124831, 1590370, 2238095, 3134927
Offset: 1
Showing 1-10 of 13 results.
Comments