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A325770
Number of distinct nonempty contiguous subsequences of the integer partition with Heinz number n.
19
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, 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, 3, 6, 1, 11, 1, 3, 5, 5, 3, 6, 1, 9, 4, 3, 1, 9, 3, 3, 3
OFFSET
1,4
COMMENTS
After a(1) = 0, first differs from A305611 at a(42) = 6, A305611(42) = 7.
The Heinz number of an integer partition (y_1,...,y_k) is prime(y_1)*...*prime(y_k).
FORMULA
a(n) = A335519(n) - 1.
EXAMPLE
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).
MATHEMATICA
Table[Length[Union[ReplaceList[If[n==1, {}, Flatten[Cases[FactorInteger[n], {p_, k_}:>Table[PrimePi[p], {k}]]]], {___, s__, ___}:>{s}]]], {n, 30}]
KEYWORD
nonn
AUTHOR
Gus Wiseman, May 20 2019
EXTENSIONS
Name corrected by Gus Wiseman, Jun 27 2020
STATUS
approved