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Number of distinct nonempty contiguous subsequences of the integer partition with Heinz number n.
19

%I #11 Jun 27 2020 21:27:19

%S 0,1,1,2,1,3,1,3,2,3,1,5,1,3,3,4,1,5,1,5,3,3,1,7,2,3,3,5,1,6,1,5,3,3,

%T 3,8,1,3,3,7,1,6,1,5,5,3,1,9,2,5,3,5,1,7,3,7,3,3,1,9,1,3,5,6,3,6,1,5,

%U 3,6,1,11,1,3,5,5,3,6,1,9,4,3,1,9,3,3,3

%N Number of distinct nonempty contiguous subsequences of the integer partition with Heinz number n.

%C After a(1) = 0, first differs from A305611 at a(42) = 6, A305611(42) = 7.

%C The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k).

%F a(n) = A335519(n) - 1.

%e The a(84) = 9 distinct nonempty contiguous subsequences of (4,2,1,1) are (1), (2), (4), (1,1), (2,1), (4,2), (2,1,1), (4,2,1), (4,2,1,1).

%t Table[Length[Union[ReplaceList[If[n==1,{},Flatten[Cases[FactorInteger[n],{p_,k_}:>Table[PrimePi[p],{k}]]]],{___,s__,___}:>{s}]]],{n,30}]

%Y Cf. A002865, A103295, A112798, A124771, A276024, A325765, A325768, A325769, A335519, A335838.

%K nonn

%O 1,4

%A _Gus Wiseman_, May 20 2019

%E Name corrected by _Gus Wiseman_, Jun 27 2020