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A332889 a(n) = number of strict partition numbers >1 that are proper divisors of the n-th strict partition number. 1
0, 0, 0, 1, 0, 2, 2, 2, 4, 2, 3, 1, 1, 3, 1, 1, 5, 4, 3, 0, 3, 1, 1, 3, 8, 3, 5, 3, 4, 6, 5, 6, 3, 2, 7, 10, 1, 1, 9, 2, 4, 3, 7, 11, 3, 6, 9, 1, 0, 1, 9, 3, 3, 2, 1, 6, 11, 8, 2, 1, 7, 2, 6, 2, 4, 12, 3, 0, 4, 8, 4, 4, 1, 7, 0, 1, 9, 7, 5, 5, 1, 1, 6, 5, 4 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,6

COMMENTS

Let p(n) = number of strict partitions of n.  Then p(11) = 12, which is divisible by these 6 strict partition numbers: p(2) = 1, p(3) = 2, p(5) = 3, p(6) = 4, p(8) = 6, and p(11) = 12; discounting 1 and 12 leaves a(11) = 4 divisors.

LINKS

Table of n, a(n) for n=3..87.

FORMULA

a(n) = A332888(n) - 2 for n >= 3.

MATHEMATICA

p[n_] := PartitionsQ[n]; t[n_] := Table[p[k], {k, 0, n}]

-2+Table[Length[Intersection[t[n], Divisors[p[n]]]], {n, 3, 130}]

CROSSREFS

Cf. A000009 (strict partition numbers), A322887, A332888.

Sequence in context: A240131 A029640 A029658 * A239452 A069930 A086327

Adjacent sequences:  A332886 A332887 A332888 * A332890 A332891 A332892

KEYWORD

nonn

AUTHOR

Clark Kimberling, Mar 11 2020

STATUS

approved

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Last modified October 26 02:14 EDT 2021. Contains 348256 sequences. (Running on oeis4.)