A143269 Triangle read by rows, A127648 * A000012 * A130207, 1<=k<=n.
1, 2, 2, 3, 3, 6, 4, 4, 8, 8, 5, 5, 10, 10, 20, 6, 6, 12, 12, 24, 12, 7, 7, 14, 14, 28, 14, 42, 8, 8, 16, 16, 32, 16, 48, 32, 9, 9, 18, 18, 36, 18, 54, 36, 54, 10, 10, 20, 20, 40, 20, 60, 40, 60, 40, 11, 11, 22, 22, 44, 22, 66, 44, 66, 44, 110
Offset: 1
Examples
First few rows of the triangle = 1; 2, 2; 3, 3, 6; 4, 4, 8, 8; 5, 5, 10, 10, 20; 6, 6, 12, 12, 24, 12; 7, 7, 14, 1428, 14, 42; ... Row 5 = (5, 5, 10, 10, 20) = (5*1, 5*1, 5*2, 5*2, 5*4); where phi(k) = (1, 1, 2, 2, 4,...).
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