A332004 Number of compositions (ordered partitions) of n into distinct and relatively prime parts.
1, 1, 0, 2, 2, 4, 8, 12, 16, 24, 52, 64, 88, 132, 180, 344, 416, 616, 816, 1176, 1496, 2736, 3232, 4756, 6176, 8756, 11172, 15576, 24120, 30460, 41456, 55740, 74440, 97976, 130192, 168408, 256464, 315972, 429888, 558192, 749920, 958264, 1274928, 1621272, 2120288, 3020256
Offset: 0
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Examples
a(6) = 8 because we have [5, 1], [3, 2, 1], [3, 1, 2], [2, 3, 1], [2, 1, 3], [1, 5], [1, 3, 2] and [1, 2, 3]. From _Gus Wiseman_, Oct 18 2020: (Start) The a(1) = 1 through a(8) = 16 compositions (empty column indicated by dot): (1) . (1,2) (1,3) (1,4) (1,5) (1,6) (1,7) (2,1) (3,1) (2,3) (5,1) (2,5) (3,5) (3,2) (1,2,3) (3,4) (5,3) (4,1) (1,3,2) (4,3) (7,1) (2,1,3) (5,2) (1,2,5) (2,3,1) (6,1) (1,3,4) (3,1,2) (1,2,4) (1,4,3) (3,2,1) (1,4,2) (1,5,2) (2,1,4) (2,1,5) (2,4,1) (2,5,1) (4,1,2) (3,1,4) (4,2,1) (3,4,1) (4,1,3) (4,3,1) (5,1,2) (5,2,1) (End)
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Programs
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Mathematica
Table[Length[Select[Join@@Permutations/@IntegerPartitions[n],UnsameQ@@#&&GCD@@#<=1&]],{n,0,15}] (* Gus Wiseman, Oct 18 2020 *)
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