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A332004 Number of compositions (ordered partitions) of n into distinct and relatively prime parts. 15

%I #13 Oct 21 2020 22:49:35

%S 1,1,0,2,2,4,8,12,16,24,52,64,88,132,180,344,416,616,816,1176,1496,

%T 2736,3232,4756,6176,8756,11172,15576,24120,30460,41456,55740,74440,

%U 97976,130192,168408,256464,315972,429888,558192,749920,958264,1274928,1621272,2120288,3020256

%N Number of compositions (ordered partitions) of n into distinct and relatively prime parts.

%C Moebius transform of A032020.

%C Ranking these compositions using standard compositions (A066099) gives the intersection of A233564 (strict) with A291166 (relatively prime). - _Gus Wiseman_, Oct 18 2020

%H Alois P. Heinz, <a href="/A332004/b332004.txt">Table of n, a(n) for n = 0..10000</a>

%H <a href="/index/Com#comp">Index entries for sequences related to compositions</a>

%e 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].

%e From _Gus Wiseman_, Oct 18 2020: (Start)

%e The a(1) = 1 through a(8) = 16 compositions (empty column indicated by dot):

%e (1) . (1,2) (1,3) (1,4) (1,5) (1,6) (1,7)

%e (2,1) (3,1) (2,3) (5,1) (2,5) (3,5)

%e (3,2) (1,2,3) (3,4) (5,3)

%e (4,1) (1,3,2) (4,3) (7,1)

%e (2,1,3) (5,2) (1,2,5)

%e (2,3,1) (6,1) (1,3,4)

%e (3,1,2) (1,2,4) (1,4,3)

%e (3,2,1) (1,4,2) (1,5,2)

%e (2,1,4) (2,1,5)

%e (2,4,1) (2,5,1)

%e (4,1,2) (3,1,4)

%e (4,2,1) (3,4,1)

%e (4,1,3)

%e (4,3,1)

%e (5,1,2)

%e (5,2,1)

%e (End)

%t Table[Length[Select[Join@@Permutations/@IntegerPartitions[n],UnsameQ@@#&&GCD@@#<=1&]],{n,0,15}] (* _Gus Wiseman_, Oct 18 2020 *)

%Y Cf. A007360, A032020, A108700, A302698.

%Y A000740 is the non-strict version.

%Y A078374 is the unordered version (non-strict: A000837).

%Y A101271*6 counts these compositions of length 3 (non-strict: A000741).

%Y A337561/A337562 is the pairwise coprime instead of relatively prime version (non-strict: A337462/A101268).

%Y A289509 gives the Heinz numbers of relatively prime partitions.

%Y A333227/A335235 ranks pairwise coprime compositions.

%Y Cf. A001523, A178472, A216652, A289508, A291166, A333228.

%K nonn

%O 0,4

%A _Ilya Gutkovskiy_, Feb 04 2020

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