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%I #15 Jan 16 2020 13:27:42
%S 1,2,2,3,2,3,4,4,3,4,5,4,6,4,5,6,6,6,8,5,6,7,6,6,8,10,6,7,8,8,6,8,10,
%T 12,7,8,9,8,9,8,10,12,14,8,9,10,10,9,12,10,12,14,16,9,10,11,10,12,12,
%U 15,12,14,16,18,10,11,12,12,12,12,15,18,14,16,18,20
%N Table of A(n,k) read by antidiagonals, where A(1,k)=k; A(n,k) is the least multiple of n >= A(n-1,k).
%C The main diagonal is conjectured to be A166447.
%e Table begins:
%e 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, ...
%e 2, 2, 4, 4, 6, 6, 8, 8, 10, 10, 12, 12, 14, 14, 16, ...
%e 3, 3, 6, 6, 6, 6, 9, 9, 12, 12, 12, 12, 15, 15, 18, ...
%e 4, 4, 8, 8, 8, 8, 12, 12, 12, 12, 12, 12, 16, 16, 20, ...
%e 5, 5, 10, 10, 10, 10, 15, 15, 15, 15, 15, 15, 20, 20, 20, ...
%e 6, 6, 12, 12, 12, 12, 18, 18, 18, 18, 18, 18, 24, 24, 24, ...
%e 7, 7, 14, 14, 14, 14, 21, 21, 21, 21, 21, 21, 28, 28, 28, ...
%e 8, 8, 16, 16, 16, 16, 24, 24, 24, 24, 24, 24, 32, 32, 32, ...
%e 9, 9, 18, 18, 18, 18, 27, 27, 27, 27, 27, 27, 36, 36, 36, ...
%t A[1, k_] := A[1, k] = k; A[n_, k_] := A[n, k] = Module[{m = 1}, While[m*n < A[n - 1, k], m++]; m*n]; Table[A[n - k + 1, k], {n, 1, 12}, {k, n, 1, -1}] // Flatten (* _Amiram Eldar_, Jan 03 2020 *)
%Y Cf. A166447.
%K nonn,tabl
%O 1,2
%A _Ali Sada_, Dec 13 2019