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Number of ways to split a strict integer partition of n into contiguous subsequences all having different sums.
13

%I #4 Jul 11 2020 07:38:50

%S 1,1,1,3,3,5,8,11,14,21,30,37,51,66,86,120,146,186,243,303,378,495,

%T 601,752,927,1150,1395,1741,2114,2571,3134,3788,4541,5527,6583,7917,

%U 9511,11319,13448,16040,18996,22455,26589,31317,36844,43518,50917,59655,69933

%N Number of ways to split a strict integer partition of n into contiguous subsequences all having different sums.

%H Gus Wiseman, <a href="/A038041/a038041.txt">Sequences counting and ranking multiset partitions whose part lengths, sums, or averages are constant or strict.</a>

%e The a(1) = 1 through a(7) = 14 splits:

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

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

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

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

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

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

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

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

%e (4),(2,1)

%e (4,2),(1)

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

%t splits[dom_]:=Append[Join@@Table[Prepend[#,Take[dom,i]]&/@splits[Drop[dom,i]],{i,Length[dom]-1}],{dom}];

%t Table[Sum[Length[Select[splits[ctn],UnsameQ@@Total/@#&]],{ctn,Select[IntegerPartitions[n],UnsameQ@@#&]}],{n,0,30}]

%Y The version with equal instead of different sums is A318683.

%Y Starting with a composition gives A336127.

%Y Starting with a strict composition gives A336128.

%Y Starting with a partition gives A336131.

%Y Partitions of partitions are A001970.

%Y Partitions of compositions are A075900.

%Y Compositions of compositions are A133494.

%Y Compositions of partitions are A323583.

%Y Cf. A006951, A063834, A279786, A305551, A316245, A317715, A323433, A336130, A336134, A336135.

%K nonn

%O 0,4

%A _Gus Wiseman_, Jul 11 2020