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A114374
Number of partitions of n into parts that are not squarefree.
23
1, 0, 0, 0, 1, 0, 0, 0, 2, 1, 0, 0, 3, 1, 0, 0, 5, 2, 2, 0, 7, 3, 2, 0, 11, 6, 4, 3, 15, 8, 6, 3, 22, 13, 11, 6, 34, 18, 15, 9, 46, 27, 24, 17, 64, 43, 33, 23, 89, 60, 51, 37, 124, 84, 78, 51, 166, 119, 109, 78, 226, 168, 152, 118, 300, 228, 215, 166, 404, 313, 300, 230, 546, 421, 409
OFFSET
0,9
COMMENTS
a(A078135(n)) = 0; a(A078137(n)) > 0.
LINKS
FORMULA
a(n) = A000041(n) - A073576(n) - A117395(n). - Reinhard Zumkeller, Mar 11 2006
G.f.: Product_{k>=1} (1 - mu(k)^2*x^k)/(1 - x^k), where mu(k) is the Moebius function (A008683). - Ilya Gutkovskiy, Dec 30 2016
EXAMPLE
a(12) = #{2*2*3, 2*2*2 + 2*2, 2*2 + 2*2 + 2*2} = 3;
a(13) = #{3*3 + 2*2} = 1.
MAPLE
with(numtheory):
b:= proc(n, i) option remember;
`if`(n=0, 1, `if`(i<1, 0, b(n, i-1)+
`if`(i>n or issqrfree(i), 0, b(n-i, i))))
end:
a:= n-> b(n$2):
seq(a(n), n=0..100); # Alois P. Heinz, Jun 03 2015
MATHEMATICA
b[n_, i_] := b[n, i] = If[n==0, 1, If[i<1, 0, b[n, i-1] + If[i>n || SquareFreeQ[i], 0, b[n-i, i]]]]; a[n_] := b[n, n]; Table[a[n], {n, 0, 100}] (* Jean-François Alcover, Jun 30 2015, after Alois P. Heinz *)
PROG
(Haskell)
a114374 = p a013929_list where
p _ 0 = 1
p ks'@(k:ks) m = if m < k then 0 else p ks' (m - k) + p ks m
-- Reinhard Zumkeller, Jun 01 2015
CROSSREFS
Cf. A256012.
Sequence in context: A136263 A105593 A029371 * A111505 A109264 A322393
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Feb 09 2006
EXTENSIONS
Offset changed and a(0)=1 prepended by Reinhard Zumkeller, Jun 01 2015
STATUS
approved