A236002
Number of overcompositions of n.
Original entry on oeis.org
1, 2, 4, 12, 26, 60, 144, 324, 728, 1602, 3576, 7808, 17068, 36908, 79520, 170704, 364794, 777036, 1649456, 3491188, 7367544, 15513336, 32584648, 68307264, 142904080, 298448914, 622235060, 1295320004, 2692583916, 5589586996, 11588905844, 23999052692
Offset: 0
For n = 4 the 26 overcompositions of 4 are: [4], [4'], [1,3], [1',3], [1,3'], [1',3'], [2,2], [2',2], [1,1,2], [1',1,2], [1,1,2'], [1',1,2'], [3,1], [3',1], [3,1'], [3',1'], [1,2,1], [1',2,1], [1,2',1], [1',2',1], [2,1,1], [2',1,1], [2,1',1], [2',1',1], [1,1,1,1], [1',1,1,1].
a(7) corrected and more terms added,
Joerg Arndt, Jan 20 2014
A235790
Triangle read by rows: T(n,k) = 2^k*A116608(n,k), n>=1, k>=1.
Original entry on oeis.org
2, 4, 4, 4, 6, 8, 4, 20, 8, 24, 8, 4, 44, 16, 8, 52, 40, 6, 68, 80, 8, 88, 120, 16, 4, 108, 200, 32, 12, 116, 296, 80, 4, 148, 416, 160, 8, 176, 536, 320, 8, 176, 776, 480, 32, 10, 220, 936, 832, 64, 4, 236, 1232, 1232, 160, 12, 272, 1472, 1872, 320
Offset: 1
Triangle begins:
2;
4;
4, 4;
6, 8;
4, 20;
8, 24, 8;
4, 44, 16;
8, 52, 40;
6, 68, 80;
8, 88, 120, 16;
4, 108, 200, 32;
12, 116, 296, 80;
4, 148, 416, 160;
8, 176, 536, 320;
8, 176, 776, 480, 32;
10, 220, 936, 832, 64;
4, 236, 1232, 1232, 160;
12, 272, 1472, 1872, 320;
4, 284, 1880, 2592, 640;
12, 324, 2216, 3632, 1152;
8, 328, 2704, 4944, 1856, 64;
...
Cf.
A000217,
A003056,
A116608,
A196020,
A211971,
A235792,
A235793,
A235797,
A235798,
A235999,
A236000,
A236001.
-
b:= proc(n, i) option remember; `if`(n=0, 1, `if`(i<1, 0,
expand(b(n, i-1)+add(x*b(n-i*j, i-1), j=1..n/i))))
end:
T:= n->(p->seq(2^i*coeff(p, x, i), i=1..degree(p)))(b(n$2)):
seq(T(n), n=1..20); # Alois P. Heinz, Jan 20 2014
-
b[n_, i_] := b[n, i] = If[n == 0, 1, If[i<1, 0, Expand[b[n, i-1] + Sum[x*b[n-i*j, i-1], {j, 1, n/i}]]]]; T[n_] := Function[p, Table[2^i * Coefficient[p, x, i], {i, 1, Exponent[p, x]}]][b[n, n]]; Table[T[n], {n, 1, 20}] // Flatten (* Jean-François Alcover, Oct 20 2016, after Alois P. Heinz *)
A235998
Triangle read by rows: T(n,k) is the number of compositions of n having k distinct parts (n>=1, 1<=k<=floor((sqrt(1+8*n)-1)/2)).
Original entry on oeis.org
1, 2, 2, 2, 3, 5, 2, 14, 4, 22, 6, 2, 44, 18, 4, 68, 56, 3, 107, 146, 4, 172, 312, 24, 2, 261, 677, 84, 6, 396, 1358, 288, 2, 606, 2666, 822, 4, 950, 5012, 2226, 4, 1414, 9542, 5304, 120, 5, 2238, 17531, 12514, 480, 2, 3418, 32412, 27904, 1800, 6, 5411, 58995, 61080, 5580
Offset: 1
Triangle begins:
1;
2;
2, 2;
3, 5;
2, 14;
4, 22, 6;
2, 44, 18;
4, 68, 56;
3, 107, 146;
4, 172, 312, 24;
2, 261, 677, 84;
6, 396, 1358, 288;
2, 606, 2666, 822;
4, 950, 5012, 2226;
4, 1414, 9542, 5304, 120;
5, 2238, 17531, 12514, 480;
2, 3418, 32412, 27904, 1800;
6, 5411, 58995, 61080, 5580;
...
-
b:= proc(n, i, p) option remember; `if`(n=0, p!, `if`(i<1, 0,
expand(add(b(n-i*j, i-1, p+j)/j!*`if`(j=0, 1, x), j=0..n/i))))
end:
T:= n-> (p-> seq(coeff(p, x, i), i=1..degree(p)))(b(n$2, 0)):
seq(T(n), n=1..25); # Alois P. Heinz, Jan 20 2014, revised May 25 2014
-
b[n_, i_, p_] := b[n, i, p] = If[n==0, p!, If[i<1, 0, Sum[b[n-i*j, i-1, p+ j]/j!*If[j==0, 1, x], {j, 0, n/i}]]]; T[n_] := Function[p, Table[ Coefficient[p, x, i], {i, 1, Exponent[p, x]}]][b[n, n, 0]]; Table[T[n], {n, 1, 25}] // Flatten (* Jean-François Alcover, Dec 10 2015, after Alois P. Heinz *)
A236625
Total number of parts in all overcompositions of n.
Original entry on oeis.org
0, 2, 6, 24, 66, 180, 496, 1272, 3202, 7798, 18980, 45076, 106288, 246956, 568776, 1299184, 2944654, 6630660, 14838606, 33026000, 73126376, 161198136, 353812612, 773645124, 1685548792, 3660364490, 7924414752, 17107225340, 36832846344, 79107019964, 169505684844
Offset: 0
For n = 3 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 24 parts, so a(3) = 24.
-
b:= proc(n, i, p) option remember; `if`(n=0, [p!, 0],
`if`(i<1, 0, add((p-> p+[0, p[1]*j])(1/j!*
`if`(j>0, 2, 1)*b(n-i*j, i-1, p+j)), j=0..n/i)))
end:
a:= n-> b(n$2, 0)[2]:
seq(a(n), n=0..35); # Alois P. Heinz, Apr 28 2016
-
b[n_, i_, p_] := b[n, i, p] = If[n == 0, {p!, 0}, If[i < 1, {0, 0}, Sum[# + {0, #[[1]]*j}&[1/j!*If[j > 0, 2, 1]*b[n - i*j, i - 1, p + j]], {j, 0, n/i}]]];
a[n_] := b[n, n, 0][[2]];
Table[a[n], {n, 0, 35}] (* Jean-François Alcover, Nov 03 2022, after Alois P. Heinz *)
A236626
Sum of all parts of all overcompositions of n.
Original entry on oeis.org
2, 8, 36, 104, 300, 864, 2268, 5824, 14418, 35760, 85888, 204816, 479804, 1113280, 2560560, 5836704, 13209612, 29690208, 66332572, 147350880, 325780056, 716862256, 1571067072, 3429697920, 7461222850, 16178111560, 34973640108, 75392349648
Offset: 1
For n = 3 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], hence the sum of all parts is 3+3+1+2+1+2+1+2+1+2+2+1+2+1+2+1+2+1+1+1+1+1+1+1 = 3*12 = 36, so a(3) = 36.
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