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A325765 Number of integer partitions of n with a unique consecutive subsequence summing to every positive integer from 1 to n. 5

%I #5 May 21 2019 22:05:27

%S 1,1,1,2,1,3,1,3,2,3,1,5,1,3,3,4,1,5,1,5,3,3,1,7,2,3,3,5,1,7,1,5,3,3,

%T 3,8,1,3,3,7,1,7,1,5,5,3,1,9,2,5,3

%N Number of integer partitions of n with a unique consecutive subsequence summing to every positive integer from 1 to n.

%C After a(0) = 1, same as A032741(n + 1) (number of proper divisors of n + 1).

%C The Heinz numbers of these partitions are given by A325764.

%e The a(1) = 1 through a(13) = 3 partitions:

%e (1) (11) (21) (1111) (221) (111111) (2221) (3311)

%e (111) (311) (4111) (11111111)

%e (11111) (1111111)

%e .

%e (22221) (1111111111) (33311) (111111111111) (2222221)

%e (51111) (44111) (7111111)

%e (111111111) (222221) (1111111111111)

%e (611111)

%e (11111111111)

%t normQ[m_]:=Or[m=={},Union[m]==Range[Max[m]]];

%t Table[Length[Select[IntegerPartitions[n],normQ[Total/@Union[ReplaceList[#,{___,s__,___}:>{s}]]]&&UnsameQ@@Total/@Union[ReplaceList[#,{___,s__,___}:>{s}]]&]],{n,0,20}]

%Y Cf. A000041, A002033, A103295, A103300, A143823, A169942, A325676, A325683, A325768, A325769, A325770.

%K nonn,more

%O 0,4

%A _Gus Wiseman_, May 20 2019

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Last modified May 23 18:59 EDT 2024. Contains 372765 sequences. (Running on oeis4.)