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A181843 Triangle read by rows: Partial row sums of A181842.

%I A181843 #15 Jun 02 2025 03:13:30
%S A181843 1,1,3,1,3,6,1,3,8,12,1,3,8,18,23,1,3,8,20,32,38,1,3,8,20,38,66,73,1,
%T A181843 3,8,20,40,78,110,118,1,3,8,20,40,84,141,189,198,1,3,8,20,40,86,153,
%U A181843 253,308,318,1,3,8,20,40,86,159,287,409,519,530,1,3,8,20,40,86,161,299,476,728,807,819
%N A181843 Triangle read by rows: Partial row sums of A181842.
%e A181843 [1]   1
%e A181843 [2]   1   3
%e A181843 [3]   1   3   6
%e A181843 [4]   1   3   8   12
%e A181843 [5]   1   3   8   18   23
%e A181843 [6]   1   3   8   20   32   38
%e A181843 [7]   1   3   8   20   38   66   73
%p A181843 with(combstruct):
%p A181843 a181843_row := proc(n) local k,L,l,R,part;
%p A181843 R := NULL; L := 0;
%p A181843 for k from 1 to n do
%p A181843    part := iterstructs(Partition(n),size=n-k+1):
%p A181843    while not finished(part) do
%p A181843       l := nextstruct(part);
%p A181843       L := L + ilcm(op(l));
%p A181843    od;
%p A181843    R := R,L;
%p A181843 od;
%p A181843 R end:
%t A181843 t[n_, k_] := LCM @@@ IntegerPartitions[n, {n - k + 1}] // Total; row[n_] := Table[t[n, k], {k, 1, n}] // Accumulate; Table[row[n], {n, 1, 12}] // Flatten (* _Jean-François Alcover_, Jul 26 2013 *)
%Y A181843 Cf. A181842, A181844.
%K A181843 nonn,tabl
%O A181843 1,3
%A A181843 _Peter Luschny_, Dec 07 2010
%E A181843 Terms from an erroneous copy and paste transfer corrected.
%E A181843 More terms from _Jean-François Alcover_, Jul 26 2013