A236633
Number of overcompositions of n minus the number of compositions of n.
Original entry on oeis.org
0, 1, 2, 8, 18, 44, 112, 260, 600, 1346, 3064, 6784, 15020, 32812, 71328, 154320, 332026, 711500, 1518384, 3229044, 6843256, 14464760, 30487496, 64112960, 134515472, 281671698, 588680628, 1228211140, 2558366188, 5321151540, 11052034932, 22925310868
Offset: 0
For n = 3 the number of overcompositions of 3 is A236002(3) = 12 and the number of compositions of 3 is A011782(3) = 4, so a(3) = 12 - 4 = 8.
On the other hand, the 12 overcompositions of 3 are [3], [3'], [1, 2], [1', 2], [1, 2'], [1', 2'], [2, 1], [2', 1], [2, 1'], [2', 1'], [1, 1, 1], [1', 1, 1]. There are 8 overcompositions with at least one overlined part, so a(3) = 8.
A237044
Number of overcompositions of n minus the number of partitions of n.
Original entry on oeis.org
0, 1, 2, 9, 21, 53, 133, 309, 706, 1572, 3534, 7752, 16991, 36807, 79385, 170528, 364563, 776739, 1649071, 3490698, 7366917, 15512544, 32583646, 68306009, 142902505, 298446956, 622232624, 1295316994, 2692580198, 5589582431, 11588900240, 23999045850
Offset: 0
A237045
Number of overcompositions of n minus the number of overpartitions of n.
Original entry on oeis.org
0, 0, 0, 4, 12, 36, 104, 260, 628, 1448, 3344, 7464, 16564, 36180, 78480, 169232, 362732, 774172, 1645508, 3485788, 7360208, 15503432, 32571360, 68289536, 142880552, 298417848, 622194236, 1295266596, 2692514348, 5589496748, 11588789220, 23998902548
Offset: 0
Illustration of a(4) = -6 with both overcompositions and overpartitions in colexicographic order.
--------------------------------------------------------
. Overcompositions of 4 Overpartitions of 4
--------------------------------------------------------
. _ _ _ _ _ _ _ _
1 |.| | | | 1', 1, 1, 1 |.| | | | 1', 1, 1, 1
2 |_| | | | 1, 1, 1, 1 |_| | | | 1, 1, 1, 1
3 | .|.| | 2', 1', 1 | .|.| | 2', 1', 1
4 | |.| | 2, 1', 1 | |.| | 2, 1', 1
5 | .| | | 2', 1, 1 | .| | | 2', 1, 1
6 |_ _| | | 2, 1, 1 |_ _| | | 2, 1, 1
7 *|.| .| | 1', 2', 1 | .|.| 3', 1
8 *| | .| | 1, 2', 1 | |.| 3, 1
9 *|.| | | 1', 2, 1 | .| | 3', 1
10 *|_| | | 1, 2, 1 |_ _ _| | 3, 1
11 | .|.| 3', 1' | .| | 2', 2
12 | |.| 3, 1' |_ _| | 2, 2
13 | .| | 3', 1 | .| 4'
14 |_ _ _| | 3, 1 |_ _ _ _| 4
15 *|.| | .| 1', 1, 2'
16 *| | | .| 1, 1, 2'
17 *|.| | | 1', 1, 2
18 *|_| | | 1, 1, 2
19 | .| | 2', 2
20 |_ _| | 2, 2
21 *|.| .| 1', 3'
22 *| | .| 1, 3'
23 *|.| | 1', 3
24 *|_| | 1, 3
25 | .| 4'
26 |_ _ _ _| 4
.
There are 26 overcompositions of 4 and there are 14 overpartitions of 4, so the difference is a(4) = 26 - 14 = 12.
On the other hand there are 12 overcompositions of 4 that contain at least two parts in increasing order, so a(4) = 12.
A237047
Number of compositions of n minus the number of overpartitions of n.
Original entry on oeis.org
0, -1, -2, -4, -6, -8, -8, 0, 28, 102, 280, 680, 1544, 3368, 7152, 14912, 30706, 62672, 127124, 256744, 516952, 1038672, 2083864, 4176576, 8365080, 16746150, 33513608, 67055456, 134148160, 268345208, 536754288, 1073591680, 2147291036, 4294721040, 8589620784
Offset: 0
Illustration of a(4) = -6.
--------------------------------------------------------
. Compositions of 4 Overpartitions of 4
--------------------------------------------------------
. _ _ _ _ _ _ _ _
1 |_| | | | 1, 1, 1, 1 |.| | | | 1', 1, 1, 1
2 |_ _| | | 2, 1, 1 |_| | | | 1, 1, 1, 1
3 |_| | | 1, 2, 1 | .|.| | 2', 1', 1
4 |_ _ _| | 3, 1 | |.| | 2, 1', 1
5 |_| | | 1, 1, 2 | .| | | 2', 1, 1
6 |_ _| | 2, 2 |_ _| | | 2, 1, 1
7 |_| | 1, 3 | .|.| 3', 1
8 |_ _ _ _| 4 | |.| 3, 1
9 | .| | 3', 1
10 |_ _ _| | 3, 1
11 | .| | 2', 2
12 |_ _| | 2, 2
13 | .| 4'
14 |_ _ _ _| 4
.
There are 8 compositions of 4 and there are 14 overpartitions of 4, so a(4) = 8 - 14 = -6.
A335651
a(n) is the sum, over all overpartitions of n, of the non-overlined parts.
Original entry on oeis.org
1, 5, 14, 35, 74, 150, 280, 505, 875, 1470, 2402, 3850, 6034, 9300, 14120, 21131, 31220, 45619, 65930, 94374, 133892, 188350, 262904, 364350, 501459, 685762, 932200, 1259944, 1693750, 2265380, 3015152, 3994585, 5268988, 6920700, 9053748, 11798873, 15319610, 19820738, 25557560
Offset: 1
The 8 overpartitions of 3 are [3], [3'], [2,1], [2,1'], [2',1], [2',1'], [1,1,1], [1',1,1], and so a(3) = 14.
Cf.
A305102 (number of non-overlined parts).
-
my(N=44, q='q+O('q^N)); Vec( prod(k=1,N, (1+q^k)/(1-q^k)) * sum(k=1,N, k*q^k/(1-q^k)) ) \\ Joerg Arndt, Jun 18 2020
A335666
a(n) is the sum, over all overpartitions of n, of the overlined parts.
Original entry on oeis.org
1, 3, 10, 21, 46, 90, 168, 295, 511, 850, 1382, 2198, 3430, 5260, 7960, 11861, 17468, 25445, 36670, 52346, 74092, 103986, 144840, 200322, 275191, 375662, 509816, 687960, 923442, 1233340, 1639312, 2168999, 2857460, 3748772, 4898652, 6377023, 8271294, 10690830, 13771912, 17683642
Offset: 1
The 8 overpartitions of 8 are [3], [3'], [2,1], [2,1'], [2',1], [2',1'], [1,1,1], [1',1,1], and so a(3) = 10.
Cf.
A305101 (number of overlined parts).
-
my(N=44, q='q+O('q^N)); Vec( prod(k=1,N, (1+q^k)/(1-q^k)) * sum(k=1,N, k*q^k/(1+q^k)) ) \\ Joerg Arndt, Jun 18 2020
A237272
Number of overcompositions of n that contain at least two parts in increasing order and that contain at least one overlined part.
Original entry on oeis.org
0, 0, 0, 3, 9, 27, 83, 211, 522, 1222, 2874, 6496, 14593, 32185, 70423, 153024, 330195, 708933, 1514821, 3224134, 6836547, 14455648, 30475210, 64096487, 134493519, 281642590, 588642240, 1228160742, 2558300338, 5321065857, 11051923912, 22925167566
Offset: 0
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