A181850 Triangle read by rows: Partial row sums of A181851(n,k).

1, 2, 3, 3, 7, 8, 4, 12, 18, 19, 5, 25, 40, 48, 49, 6, 27, 77, 101, 111, 112, 7, 63, 129, 225, 260, 272, 273, 8, 68, 248, 408, 568, 616, 630, 631, 9, 105, 369, 801, 1126, 1370, 1433, 1449, 1450, 10, 115, 625, 1401, 2293, 2878, 3228, 3308, 3326, 3327

Offset

1,2

Links

Alois P. Heinz, Rows n = 1..25, flattened

Example

[1]   1
[2]   2    3
[3]   3    7     8
[4]   4   12    18    19
[5]   5   25    40    48    49
[6]   6   27    77   101   111   112
[7]   7   63   129   225   260   272   273

Maple

with(combstruct):
a181850_row := proc(n) local k, L, l, R, comp;
R := NULL; L := 0;
for k from 1 to n do
   comp := iterstructs(Composition(n), size=k):
   while not finished(comp) do
      l := nextstruct(comp);
      L := L + ilcm(op(l));
   od;
   R := R, L;
od;
R end:

Mathematica

c[n_, k_] := Permutations /@ IntegerPartitions[n, {k}] // Flatten[#, 1]&; t[n_, k_] := Total[LCM @@@ c[n, k]]; Table[Print[row = Table[t[n, k], {k, 1, n}] // Accumulate]; row, {n, 1, 25}] // Flatten  (* Jean-François Alcover, Feb 05 2014 *)

Crossrefs

Cf. A181849, A181851, A181854.

Sequence in context: A209768 A209169 A222294 * A335050 A062761 A117524

Adjacent sequences: A181847 A181848 A181849 * A181851 A181852 A181853

Keyword

nonn,tabl

Author

Peter Luschny, Dec 07 2010

Status

approved