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%I
%S 1,1,2,1,2,3,1,2,3,5,1,3,4,5,6,1,3,4,5,6,7,1,2,5,6,7,8,9,1,2,5,6,7,8,
%T 9,11,1,2,5,6,7,8,9,11,13,1,2,5,7,8,9,11,12,13,15,1,2,5,7,8,9,11,12,
%U 13,15,17,1,2,5,7,8,9,11,12,13,15,17,19
%N Triangle read by rows: n-th row is the lexicographically earliest n-element subset of {1,2,3,...,A347498(n)} with the property that all products i * j are distinct for i <= j.
%C Is the first column the all 1's sequence?
%e Triangle begins:
%e 1;
%e 1, 2;
%e 1, 2, 3;
%e 1, 2, 3, 5;
%e 1, 3, 4, 5, 6;
%e 1, 3, 4, 5, 6, 7;
%e 1, 2, 5, 6, 7, 8, 9;
%e 1, 2, 5, 6, 7, 8, 9, 11;
%e 1, 2, 5, 6, 7, 8, 9, 11, 13;
%e 1, 2, 5, 7, 8, 9, 11, 12, 13, 15;
%e 1, 2, 5, 7, 8, 9, 11, 12, 13, 15, 17;
%e 1, 2, 5, 7, 8, 9, 11, 12, 13, 15, 17, 19;
%e 1, 5, 6, 7, 9, 11, 13, 14, 15, 16, 17, 19, 20;
%e 1, 2, 5, 7, 11, 12, 13, 16, 17, 18, 19, 20, 21, 23;
%e ...
%Y A106683 is analogous for addition.
%Y Cf. A347498.
%K nonn,tabl
%O 1,3
%A _Peter Kagey_, Sep 03 2021
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