A083751 -id:A083751 - cp's OEIS frontend

A187219 Number of partitions of n that do not contain parts less than the smallest part of the partitions of n-1.

1, 1, 1, 2, 2, 4, 4, 7, 8, 12, 14, 21, 24, 34, 41, 55, 66, 88, 105, 137, 165, 210, 253, 320, 383, 478, 574, 708, 847, 1039, 1238, 1507, 1794, 2167, 2573, 3094, 3660, 4378, 5170, 6153, 7245, 8591, 10087, 11914, 13959, 16424, 19196, 22519, 26252, 30701, 35717

Offset: 1

Omar E. Pol, Dec 09 2011

nonn

Essentially the same as A002865, but here a(1) = 1 not 0.
Also number of regions in the last section of the set of partitions of n.
Also number of partitions of n+k that are formed by k+1 sections, k >= 0 (Cf. A194799). - Omar E. Pol, Jan 30 2012
For the definition of region see A206437. - Omar E. Pol, Aug 13 2013
Partial sums give A000041, n >= 1. - Omar E. Pol, Sep 04 2013
Also the number of partitions of n with no parts greater than the number of ones. - Spencer Miller, Jan 28 2023

			From _Omar E. Pol_, Aug 13 2013: (Start)
Illustration of initial terms as number of regions:
.                                           _ _ _ _ _ _
.                                          |_ _ _      |
.                                          |_ _ _|_    |
.                                          |_ _    |   |
.                               _ _ _ _ _  |_ _|_ _|_  |
.                              |_ _ _    |           | |
.                     _ _ _ _  |_ _ _|_  |           | |
.                    |_ _    |         | |           | |
.             _ _ _  |_ _|_  |         | |           | |
.       _ _  |_ _  |       | |         | |           | |
.   _  |_  |     | |       | |         | |           | |
.  |_|   |_|     |_|       |_|         |_|           |_|
.
.   1     1       1         2           2             4
.
(End)

Paolo Xausa, Table of n, a(n) for n = 1..10000 (terms 1..1000 from Vincenzo Librandi)
Omar E. Pol, Illustration of the seven regions of 5

Cf. A000041, A002865, A083751, A135010, A186114, A193870, A206437, A225600, A225610.

Join[{1}, Drop[CoefficientList[Series[1 / Product[(1 - x^k)^1, {k, 2, 50}], {x, 0, 50}], x], 2]] (* Vincenzo Librandi, Feb 15 2018 *)
A187219[nmax_]:=Join[{1},Differences[PartitionsP[Range[nmax]]]];
A187219[100] (* Paolo Xausa, Feb 17 2023 *)

a(n) = A083751(n) + 1. - Omar E. Pol, Mar 04 2012

a(n) = A002865(n), if n >= 2. - Omar E. Pol, Aug 13 2013

Better definition from Omar E. Pol, Sep 04 2013

A318029 Expansion of Sum_{k>=2} x^(k*(k+3)/2) / Product_{j=1..k} (1 - x^j).

Original entry on oeis.org

0, 0, 0, 0, 0, 1, 1, 2, 2, 4, 4, 6, 7, 9, 11, 14, 16, 20, 24, 28, 34, 40, 47, 55, 65, 75, 88, 102, 118, 136, 158, 180, 208, 238, 272, 311, 355, 403, 459, 521, 590, 668, 756, 852, 962, 1084, 1218, 1370, 1538, 1724, 1932, 2163, 2417, 2701, 3015, 3361, 3745, 4170, 4636, 5154, 5724

Offset: 0

Ilya Gutkovskiy, Aug 13 2018

nonn

Number of partitions of n into at least two distinct parts >= 2.

			a(9) = 4 because we have [7, 2], [6, 3], [5, 4] and [4, 3, 2].

Index entries for sequences related to partitions

Cf. A000009, A025147, A083751, A096765, A111133.

nmax = 60; CoefficientList[Series[Sum[x^(k (k + 3)/2)/Product[(1 - x^j), {j, 1, k}], {k, 2, nmax}], {x, 0, nmax}], x]
nmax = 60; CoefficientList[Series[x - 1/(1 - x) + 1/((1 + x) QPochhammer[x, x^2]), {x, 0, nmax}], x]
Join[{0, 0}, Table[-1 + Sum[(-1)^(n - k) PartitionsQ[k], {k, 0, n}], {n, 2, 60}]]

G.f.: x - 1/(1 - x) + Product_{k>=2} (1 + x^k).

a(n) = A025147(n) - 1 for n > 1.

A379720 Except a(0)=1 and a(4)=0, number of integer partitions of n with no 1's and at least two parts.

Original entry on oeis.org

1, 0, 0, 0, 0, 1, 3, 3, 6, 7, 11, 13, 20, 23, 33, 40, 54, 65, 87, 104, 136, 164, 209, 252, 319, 382, 477, 573, 707, 846, 1038, 1237, 1506, 1793, 2166, 2572, 3093, 3659, 4377, 5169, 6152, 7244, 8590, 10086, 11913, 13958, 16423, 19195, 22518, 26251, 30700, 35716

Offset: 0

Gus Wiseman, Jan 06 2025

nonn

Also partitions of n such that all parts are > 1 and have product > n.

Allowing 1's gives A114324, ranks A325037. The strict case is A318029 (except first term).

			The a(5) = 1 through a(11) = 13 partitions:
  (3,2)  (3,3)    (4,3)    (4,4)      (5,4)      (5,5)        (6,5)
         (4,2)    (5,2)    (5,3)      (6,3)      (6,4)        (7,4)
         (2,2,2)  (3,2,2)  (6,2)      (7,2)      (7,3)        (8,3)
                           (3,3,2)    (3,3,3)    (8,2)        (9,2)
                           (4,2,2)    (4,3,2)    (4,3,3)      (4,4,3)
                           (2,2,2,2)  (5,2,2)    (4,4,2)      (5,3,3)
                                      (3,2,2,2)  (5,3,2)      (5,4,2)
                                                 (6,2,2)      (6,3,2)
                                                 (3,3,2,2)    (7,2,2)
                                                 (4,2,2,2)    (3,3,3,2)
                                                 (2,2,2,2,2)  (4,3,2,2)
                                                              (5,2,2,2)
                                                              (3,2,2,2,2)

For <= instead of < we have A002865 = partitions into parts > 1.
These partitions have ranks A071904 (except initial terms).
Set a(4) = 1 to get A083751.
A000041 counts integer partitions, strict A000009.
A379668 counts partitions without 1's by sum and product.
Counting and ranking multisets by comparing sum and product:
- same: A001055, ranks A301987
- divisible: A057567, ranks A326155
- divisor: A057568, ranks A326149, see A379733
- greater than: A096276 shifted right, ranks A325038
- greater or equal: A096276, ranks A325044
- less than: A114324, ranks A325037, see A318029
- less or equal: A319005, ranks A379721, see A025147
- different: A379736, ranks A379722, see A111133
Cf. A003963, A028422, A318950, A319000, A319916, A325036, A325041, A326152, A326178, A379666, A379678.

Table[Length[Select[IntegerPartitions[n],FreeQ[#,1]&&Plus@@#

Except for n = 0 and n = 4, we have a(n) = A002865(n) - 1.

A182699 Number of emergent parts in all partitions of n.

Original entry on oeis.org

0, 0, 0, 0, 1, 1, 4, 4, 10, 12, 22, 27, 47, 56, 89, 112, 164, 205, 294, 364, 505, 630, 845, 1052, 1393, 1719, 2235, 2762, 3533, 4343, 5506, 6730, 8443, 10296, 12786, 15531, 19161, 23161, 28374, 34201, 41621, 49975, 60513, 72385, 87200, 103999, 124670, 148209

Offset: 0

Omar E. Pol, Nov 29 2010

Here the "emergent parts" of the partitions of n are defined to be the parts (with multiplicity) of all the partitions that do not contain "1" as a part, removed by one copy of the smallest part of every partition. Note that these parts are located in the head of the last section of the set of partitions of n.
Also, here the "filler parts" of the partitions of n are defined to be the parts of the last section of the set of partitions of n that are not the emergent parts.
For n >= 4, length of row n of A183152. - Omar E. Pol, Aug 08 2011
Also total number of parts of the regions that do not contain 1 as a part in the last section of the set of partitions of n (cf. A083751, A187219). - Omar E. Pol, Mar 04 2012

			For n = 6 the partitions of 6 contain four "emergent" parts: (3), (4), (2), (2), so a(6) = 4. See below the location of the emergent parts.
6
(3) + 3
(4) + 2
(2) + (2) + 2
5 + 1
3 + 2 + 1
4 + 1 + 1
2 + 2 + 1 + 1
3 + 1 + 1 + 1
2 + 1 + 1 + 1 + 1
1 + 1 + 1 + 1 + 1 + 1
For a(10) = 22 see the link for the location of the 22 "emergent parts" (colored yellow and green) and the location of the 42 "filler parts" (colored blue) in the last section of the set of partitions of 10.

Alois P. Heinz, Table of n, a(n) for n = 0..1000
Omar E. Pol, Illustration: How to build the last section of the set of partitions (copy, paste and fill)
Omar E. Pol, Illustration of the shell model of partitions (2D view)

Cf. A000041, A002865, A135010, A138121, A138135, A182700, A182709, A182740.

b:= proc(n, i) option remember; local t, h;
      if n<0 then [0, 0, 0]
    elif n=0 then [0, 1, 0]
    elif i<2 then [0, 0, 0]
    else t:= b(n, i-1); h:= b(n-i, i);
         [t[1]+h[1]+h[2], t[2], t[3]+h[3]+h[1]]
      fi
    end:
a:= n-> b(n, n)[3]:
seq (a(n), n=0..50);  # Alois P. Heinz, Oct 21 2011

b[n_, i_] := b[n, i] = Module[{t, h}, Which[n<0, {0, 0, 0}, n == 0, {0, 1, 0}, i<2 , {0, 0, 0}, True, t = b[n, i-1]; h = b[n-i, i]; Join [t[[1]] + h[[1]] + h[[2]], t[[2]], t[[3]] + h[[3]] + h[[1]] ]]]; a[n_] := b[n, n][[3]]; Table[a[n], {n, 0, 50}] (* Jean-François Alcover, Jun 18 2015, after Alois P. Heinz *)

a(n) = A138135(n) - A002865(n), n >= 1.
From Omar E. Pol, Oct 21 2011: (Start)
a(n) = A006128(n) - A006128(n-1) - A000041(n), n >= 1.
a(n) = A138137(n) - A000041(n), n >= 1. (End)
a(n) = A076276(n) - A006128(n-1), n >= 1. - Omar E. Pol, Oct 30 2011

A182709 Sum of the emergent parts of the partitions of n.

Original entry on oeis.org

0, 0, 0, 2, 3, 11, 14, 33, 45, 81, 109, 185, 237, 372, 490, 715, 928, 1326, 1693, 2348, 2998, 4032, 5119, 6795, 8530, 11132, 13952, 17927, 22314, 28417, 35126, 44279, 54532, 68062, 83422, 103427, 126063, 155207, 188506, 230547, 278788, 339223, 408482

Offset: 1

Omar E. Pol, Nov 28 2010, Nov 29 2010

Here the "emergent parts" of the partitions of n are defined to be the parts (with multiplicity) of all the partitions that do not contain "1" as a part, removed by one copy of the smallest part of every partition. Note that these parts are located in the head of the last section of the set of partitions of n. For more information see A182699.

Also total sum of parts of the regions that do not contain 1 as a part in the last section of the set of partitions of n (Cf. A083751, A187219). - Omar E. Pol, Mar 04 2012

			For n=7 the partitions of 7 that do not contain "1" as a part are
7
4 + 3
5 + 2
3 + 2 + 2
Then remove one copy of the smallest part of every partition. The rest are the emergent parts:
.,
4, .
5, .
3, 2, .
The sum of these parts is 4 + 5 + 3 + 2 = 14, so a(7)=14.
For n=10 the illustration in the link shows the location of the emergent parts (colored yellow and green) and the location of the filler parts (colored blue) in the last section of the set of partitions of 10.

Vaclav Kotesovec, Table of n, a(n) for n = 1..10000 (terms 1..1000 from Jason Kimberley)
Omar E. Pol, Illustration: How to build the last section of the set of partitions (copy, paste and fill)
Omar E. Pol, Illustration of the shell model of partitions (2D view)

Cf. A000041, A135010, A138121, A138879, A138880, A182699, A182703, A182708, A182740, A182742, A182743.

Row sums of A183152.

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:
c:= proc(n, i, k) option remember;
      if n<0 then 0
    elif n=0 then k
    elif i<2 then 0
    else c(n, i-1, k) +c(n-i, i, i)
      fi
    end:
a:= n-> n*b(n, n) - c(n, n, 0):
seq(a(n), n=1..40);  #  Alois P. Heinz, Dec 01 2010

f[n_]:=Total[Flatten[Most/@Select[IntegerPartitions[n],!MemberQ[#,1]&]]]; Table[f[i],{i,50}] (* Harvey P. Dale, Dec 28 2010 *)
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]]; c[n_, i_, k_] := c[n, i, k] = Which[n<0, 0, n==0, k, i<2, 0, True, c[n, i-1, k] + c[n-i, i, i]]; a[n_] := n*b[n, n] - c[n, n, 0]; Table[a[n], {n, 1, 40}] (* Jean-François Alcover, Oct 08 2015, after Alois P. Heinz *)

a(n) = A138880(n) - A182708(n).
a(n) = A066186(n) - A066186(n-1) - A046746(n) = A138879(n) - A046746(n). - Omar E. Pol, Aug 01 2013
a(n) ~ Pi * exp(Pi*sqrt(2*n/3)) / (12*sqrt(2*n)) * (1 - (3*sqrt(3/2)/Pi + 13*Pi/(24*sqrt(6)))/sqrt(n)). - Vaclav Kotesovec, Jan 03 2019, extended Jul 05 2019

More terms from Alois P. Heinz, Dec 01 2010

A000094 Number of trees of diameter 4.

Original entry on oeis.org

0, 0, 0, 0, 1, 2, 5, 8, 14, 21, 32, 45, 65, 88, 121, 161, 215, 280, 367, 471, 607, 771, 980, 1232, 1551, 1933, 2410, 2983, 3690, 4536, 5574, 6811, 8317, 10110, 12276, 14848, 17941, 21600, 25977, 31146, 37298, 44542, 53132, 63218, 75131, 89089

Offset: 1

N. J. A. Sloane

nonn

Number of partitions of n-1 with at least two parts of size 2 or larger. - Franklin T. Adams-Watters, Jan 13 2006
Also equal to the number of partitions p of n-1 such that max(p)-min(p) > 1. Example: a(7)=5 because we have [5,1],[4,2],[4,1,1],[3,2,1] and [3,1,1,1]. - Giovanni Resta, Feb 06 2006
Also number of partitions of n-1 with at least two parts that are smaller than the largest part. Example: a(7)=5 because we have [4,1,1],[3,2,1],[3,1,1,1],[2,2,1,1,1] and [2,1,1,1,1]. - Emeric Deutsch, May 01 2006
Also number of regions of n-1 that do not contain 1 as a part, n >= 2 (cf. A186114, A206437). - Omar E. Pol, Dec 01 2011
Also rank of the last region of n-1 multiplied by -1, n >= 2 (cf. A194447). - Omar E. Pol, Feb 11 2012
Also sum of ranks of the regions of n-1 that contain emergent parts, n >= 2 (cf. A182699). For the definition of "regions of n" see A206437. - Omar E. Pol, Feb 21 2012

			From _Gus Wiseman_, Apr 12 2019: (Start)
The a(5) = 1 through a(9) = 14 partitions of n-1 with at least two parts of size 2 or larger, or non-hooks, are the following. The Heinz numbers of these partitions are given by A105441.
  (22)  (32)   (33)    (43)     (44)
        (221)  (42)    (52)     (53)
               (222)   (322)    (62)
               (321)   (331)    (332)
               (2211)  (421)    (422)
                       (2221)   (431)
                       (3211)   (521)
                       (22111)  (2222)
                                (3221)
                                (3311)
                                (4211)
                                (22211)
                                (32111)
                                (221111)
The a(5) = 1 through a(9) = 14 partitions of n-1 whose maximum part minus minimum part is at least 2 are the following. The Heinz numbers of these partitions are given by A307516.
  (31)  (41)   (42)    (52)     (53)
        (311)  (51)    (61)     (62)
               (321)   (331)    (71)
               (411)   (421)    (422)
               (3111)  (511)    (431)
                       (3211)   (521)
                       (4111)   (611)
                       (31111)  (3221)
                                (3311)
                                (4211)
                                (5111)
                                (32111)
                                (41111)
                                (311111)
The a(5) = 1 through a(9) = 14 partitions of n-1 with at least two parts that are smaller than the largest part are the following. The Heinz numbers of these partitions are given by A307517.
  (211)  (311)   (321)    (322)     (422)
         (2111)  (411)    (421)     (431)
                 (2211)   (511)     (521)
                 (3111)   (3211)    (611)
                 (21111)  (4111)    (3221)
                          (22111)   (3311)
                          (31111)   (4211)
                          (211111)  (5111)
                                    (22211)
                                    (32111)
                                    (41111)
                                    (221111)
                                    (311111)
                                    (2111111)
(End)

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

Christian G. Bower, Table of n, a(n) for n = 1..500
J. Riordan, Enumeration of trees by height and diameter, IBM J. Res. Dev. 4 (1960), 473-478.
J. Riordan, The enumeration of trees by height and diameter, IBM Journal 4 (1960), 473-478. (Annotated scanned copy)
Miloslav Znojil, Perturbation theory near degenerate exceptional points, arXiv:2008.00479 [math-ph], 2020.
Index entries for sequences related to trees

Cf. A000041, A206437, A034853, A000147 (diameter 5).

Cf. A006918, A083751, A084835, A105441, A115720, A257990, A307516, A307517, A325164.

g:=x/product(1-x^j,j=1..70)-x-x^2/(1-x)^2: gser:=series(g,x=0,48): seq(coeff(gser,x,n),n=1..46); # Emeric Deutsch, May 01 2006
A000094 := proc(n)
    combinat[numbpart](n-1)-n+1 ;
end proc: # R. J. Mathar, May 17 2016

t=Table[PartitionsP[n]-n,{n,0,45}];
ReplacePart[t,0,1]
(* Clark Kimberling, Mar 05 2012 *)
CoefficientList[1/QPochhammer[x]-x/(1-x)^2-1+O[x]^50, x] (* Jean-François Alcover, Feb 04 2016 *)

a(n+1) = A000041(n)-n for n>0. - John W. Layman
G.f.: x/product(1-x^j,j=1..infinity)-x-x^2/(1-x)^2. - Emeric Deutsch, May 01 2006
G.f.: sum(sum(x^(i+j+1)/product(1-x^k, k=i..j), i=1..j-2), j=3..infinity). - Emeric Deutsch, May 01 2006
a(n+1) = Sum_{m=1..n} A083751(m). - Gregory Gerard Wojnar, Oct 13 2020

More terms from Franklin T. Adams-Watters, Jan 13 2006

A212551 Number of partitions T(n,k) of n containing at least one other part m-k if m is the largest part; triangle T(n,k), n>=0, 0<=k<=n.

Original entry on oeis.org

1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 2, 1, 1, 0, 0, 2, 3, 1, 1, 0, 0, 4, 3, 3, 1, 1, 0, 0, 4, 6, 4, 3, 1, 1, 0, 0, 7, 7, 7, 4, 3, 1, 1, 0, 0, 8, 11, 9, 8, 4, 3, 1, 1, 0, 0, 12, 13, 15, 10, 8, 4, 3, 1, 1, 0, 0, 14, 20, 18, 17, 11, 8, 4, 3, 1, 1, 0, 0

Offset: 0

Alois P. Heinz, May 20 2012

Reversed rows converge to A024786.

			T(4,0) = 2: [1,1,1,1], [2,2].
T(4,1) = 1: [2,1,1].
T(5,1) = 3: [2,1,1,1], [2,2,1], [3,2].
T(6,2) = 3: [3,1,1,1], [3,2,1], [4,2].
T(7,2) = 4: [3,1,1,1,1], [3,2,1,1], [3,3,1], [4,2,1].
T(8,4) = 3: [5,1,1,1], [5,2,1], [6,2].
Triangle T(n,k) begins:
1;
0, 0;
1, 0, 0;
1, 1, 0, 0;
2, 1, 1, 0, 0;
2, 3, 1, 1, 0, 0;
4, 3, 3, 1, 1, 0, 0;
4, 6, 4, 3, 1, 1, 0, 0;
7, 7, 7, 4, 3, 1, 1, 0, 0;

Alois P. Heinz, Rows n = 0..140, flattened
Wikipedia, Kronecker delta

Columns k=0-10 give: A002865, A083751(n+1), A119907, A212543, A212544, A212545, A212546, A212547, A212548, A212549, A212550.
Row sums give A000070(n-2) for n>1.
Cf. A024786.

b:= proc(n, i) option remember;
      `if`(n=0 or i=1, 1, b(n, i-1)+`if`(i>n, 0, b(n-i, i)))
    end:
T:= (n, k)-> `if`(n=0 and k=0, 1,
    add(b(n-2*m-k, min(n-2*m-k, m+k)), m=1..(n-k)/2)):
seq(seq(T(n, k), k=0..n), n=0..14);

b[n_, i_] := b[n, i] = If[n == 0 || i == 1, 1, b[n, i-1] + If[i > n, 0, b[n-i, i]]]; t[n_, k_] := If[n == 0 && k == 0, 1, Sum[b[n-2*m-k, Min[n-2*m-k, m+k]], {m, 1, (n-k)/2}]]; Table[Table[t[n, k], {k, 0, n}], {n, 0, 14}] // Flatten (* Jean-François Alcover, Dec 13 2013, translated from Maple *)

G.f. of column k: delta_{0,k} + Sum_{i>0} x^(2*i+k) / Product_{j=1..k+i} (1-x^j), where delta is the Kronecker delta.

A320179 Regular triangle where T(n,k) is the number of unlabeled series-reduced rooted trees with n leaves in which every leaf is at height k.

Original entry on oeis.org

1, 0, 1, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 1, 3, 0, 0, 0, 0, 1, 3, 0, 0, 0, 0, 0, 1, 6, 1, 0, 0, 0, 0, 0, 1, 7, 1, 0, 0, 0, 0, 0, 0, 1, 11, 4, 0, 0, 0, 0, 0, 0, 0, 1, 13, 6, 0, 0, 0, 0, 0, 0, 0, 0, 1, 20, 16, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 23, 23, 0, 0, 0

Offset: 1

Gus Wiseman, Oct 07 2018

			Triangle begins:
  1
  0  1
  0  1  0
  0  1  1  0
  0  1  1  0  0
  0  1  3  0  0  0
  0  1  3  0  0  0  0
  0  1  6  1  0  0  0  0
  0  1  7  1  0  0  0  0  0
  0  1 11  4  0  0  0  0  0  0
  0  1 13  6  0  0  0  0  0  0  0
  0  1 20 16  0  0  0  0  0  0  0  0
  0  1 23 23  0  0  0  0  0  0  0  0  0
  0  1 33 46  0  0  0  0  0  0  0  0  0  0
The T(10,3) = 4 rooted trees:
   (((oo)(oo))((oo)(oooo)))
   (((oo)(oo))((ooo)(ooo)))
   (((oo)(ooo))((oo)(ooo)))
  (((oo)(oo))((oo)(oo)(oo)))

Andrew Howroyd, Table of n, a(n) for n = 1..1275 (rows 1..50)

Row sums are A120803. Third column is A083751. An irregular version is A320221.
Cf. A000669, A001678, A048816, A079500, A119262, A244925, A316655, A319312.
Cf. A316624, A320154, A320155, A320160, A320172, A320173.

qurt[n_]:=If[n==1,{{}},Join@@Table[Union[Sort/@Tuples[qurt/@ptn]],{ptn,Select[IntegerPartitions[n],Length[#]>1&]}]];
Table[Length[Select[qurt[n],SameQ[##,k]&@@Length/@Position[#,{}]&]],{n,14},{k,0,n-1}]

EulerT(v)={Vec(exp(x*Ser(dirmul(v, vector(#v, n, 1/n))))-1, -#v)}
T(n)={my(u=vector(n), v=vector(n), h=1); u[1]=1; while(u, v+=u*h; h*=x; u=EulerT(u)-u); vector(n, n, Vecrev(v[n], n))}
{ my(A=T(15)); for(n=1, #A, print(A[n])) } \\ Andrew Howroyd, Dec 09 2020

A196025 Total sum of parts greater than 1 in all the partitions of n except one copy of the smallest part greater than 1 of every partition.

Original entry on oeis.org

0, 0, 0, 2, 5, 16, 30, 63, 108, 189, 298, 483, 720, 1092, 1582, 2297, 3225, 4551, 6244, 8592, 11590, 15622, 20741, 27536, 36066, 47198, 61150, 79077, 101391, 129808, 164934, 209213, 263745, 331807, 415229, 518656, 644719, 799926, 988432, 1218979

Offset: 1

Omar E. Pol, Oct 27 2011

nonn

Also partial sums of A182709. Total sum of emergent parts in all partitions of all numbers <= n.

Also total sum of parts of all regions of n that do not contain 1 as a part (Cf. A083751, A187219). - Omar E. Pol, Mar 04 2012

Vaclav Kotesovec, Table of n, a(n) for n = 1..10000

Cf. A026905, A046746, A066186, A135010, A138121, A182699, A182707, A182709, A183152, A193827, A196039, A196930, A196931, A198381.

a(n) = A066186(n) - A196039(n).

a(n) ~ exp(Pi*sqrt(2*n/3)) / (4*sqrt(3)). - Vaclav Kotesovec, Jul 06 2019

A198381 Total number of parts greater than 1 in all partitions of n minus the number of partitions of n into parts each less than n.

Original entry on oeis.org

0, 0, 0, 0, 1, 2, 6, 10, 20, 32, 54, 81, 128, 184, 273, 385, 549, 754, 1048, 1412, 1917, 2547, 3392, 4444, 5837, 7556, 9791, 12553, 16086, 20429, 25935, 32665, 41108, 51404, 64190, 79721, 98882, 122043, 150417, 184618, 226239

Offset: 0

Omar E. Pol, Oct 27 2011

nonn

Also partial sums of A182699. Total number of emergent parts in all partitions of the numbers <= n.

Also total number of parts of all regions of n that do not contain 1 as a part (Cf. A083751, A187219). - Omar E. Pol, Mar 04 2012

Cf. A000041, A000065, A000070, A006128, A026905, A093694, A096541, A135010, A138121, A182699, A182707, A182709, A183152, A193827, A196930, A196931.

a(n) = A096541(n) - A000065(n) = 1 + A096541(n) - A000041(n) = 1 + A006128(n) - A000070(n).

a(n) = A006128(n) - A026905(n), n >= 1.

cp's OEIS Frontend

A187219 Number of partitions of n that do not contain parts less than the smallest part of the partitions of n-1.

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A318029 Expansion of Sum_{k>=2} x^(k*(k+3)/2) / Product_{j=1..k} (1 - x^j).

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A379720 Except a(0)=1 and a(4)=0, number of integer partitions of n with no 1's and at least two parts.

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A182699 Number of emergent parts in all partitions of n.

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A182709 Sum of the emergent parts of the partitions of n.

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A000094 Number of trees of diameter 4.

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A212551 Number of partitions T(n,k) of n containing at least one other part m-k if m is the largest part; triangle T(n,k), n>=0, 0<=k<=n.

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