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A181854 Triangle read by rows: Partial row sums of A181853(n,k).

%I A181854 #12 Jun 02 2025 03:13:36
%S A181854 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,
%T A181854 1050,1332,1392,1,29,317,1697,4942,8682,10716,11136,1,37,493,3209,
%U A181854 11502,24770,36108,41016,41856
%N A181854 Triangle read by rows: Partial row sums of A181853(n,k).
%H A181854 Alois P. Heinz, <a href="/A181854/b181854.txt">Rows n = 0..25, flattened</a>
%e A181854 [0]   1
%e A181854 [1]   1    2
%e A181854 [2]   1    4     6
%e A181854 [3]   1    7    18    24
%e A181854 [4]   1   11    42    76     88
%e A181854 [5]   1   16    97   286    468    528
%e A181854 [6]   1   22   163   556   1050   1332   1392
%p A181854 with(combstruct):
%p A181854 a181854_row := proc(n) local k,L,l,R,comb;
%p A181854 R := NULL; L := 0;
%p A181854 for k from 0 to n do
%p A181854    comb := iterstructs(Combination(n),size=k):
%p A181854    while not finished(comb) do
%p A181854       l := nextstruct(comb);
%p A181854       L := L + ilcm(op(l));
%p A181854    od;
%p A181854    R := R,L;
%p A181854 od;
%p A181854 R end:
%t A181854 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-François Alcover_, Jul 30 2013 *)
%Y A181854 Cf. A096179, A181853.
%K A181854 nonn,tabl
%O A181854 0,3
%A A181854 _Peter Luschny_, Dec 06 2010