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A181854 Triangle read by rows: Partial row sums of A181853(n,k) 5
1, 1, 2, 1, 4, 6, 1, 7, 18, 24, 1, 11, 42, 76, 88, 1, 16, 97, 286, 468, 528, 1, 22, 163, 556, 1050, 1332, 1392, 1, 29, 317, 1697, 4942, 8682, 10716, 11136, 1, 37, 493, 3209, 11502, 24770, 36108, 41016, 41856 (list; table; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Alois P. Heinz, Rows n = 0..25, flattened

EXAMPLE

[0]   1

[1]   1    2

[2]   1    4     6

[3]   1    7    18    24

[4]   1   11    42    76     88

[5]   1   16    97   286    468    528

[6]   1   22   163   556   1050   1332   1392

MAPLE

with(combstruct):

a181854_row := proc(n) local k, L, l, R, comb;

R := NULL; L := 0;

for k from 0 to n do

   comb := iterstructs(Combination(n), size=k):

   while not finished(comb) do

      l := nextstruct(comb);

      L := L + ilcm(op(l));

   od;

   R := R, L;

od;

R end:

MATHEMATICA

t[_, 0] = 1; t[n_, k_] := Sum[LCM @@ c, {c, Subsets[Range[n], {k}]}]; row[n_] := Table[t[n, k], {k, 0, n}] // Accumulate; Table[row[n], {n, 0, 8}] // Flatten (* Jean-Fran├žois Alcover, Jul 30 2013 *)

CROSSREFS

Cf. A096179, A181853.

Sequence in context: A219441 A219142 A220226 * A109822 A274292 A114192

Adjacent sequences:  A181851 A181852 A181853 * A181855 A181856 A181857

KEYWORD

nonn,tabl

AUTHOR

Peter Luschny, Dec 06 2010

STATUS

approved

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Last modified April 8 11:18 EDT 2020. Contains 333313 sequences. (Running on oeis4.)