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%I #7 Dec 11 2015 22:01:51
%S 1,2,2,2,3,4,5,7,9,16,16,22,22,34,37,46,46,57,71,79,81,103,103,106
%N Smallest k > 0 such that the products of the nonempty subsets of {k, k+1,..., k+n-1} are all distinct.
%F a(n) >= A239276(n).
%e a(5) = 3 because the range {1,...,5} is ruled out by 1*2=2, the range {2,...,6} by 2*3 = 6 and all 31 subsets of {3,...,7} give a distinct product.
%t a[1]=1; a[n_] := a[n] = Block[{k = a[n-1]}, While[Min@ Differences@ Sort[Times @@@ Rest@ Subsets@ Range[k, n+k-1]] == 0, k++]; k]; Array[a, 16]
%Y Cf. A239276, A239277.
%K nonn,more
%O 1,2
%A _Giovanni Resta_, Mar 14 2014
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