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A326626
Number of partitions of n into 10 squarefree parts.
14
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 2, 2, 4, 5, 8, 9, 13, 16, 23, 26, 35, 41, 54, 62, 79, 90, 115, 130, 161, 182, 224, 251, 303, 341, 408, 456, 539, 601, 709, 786, 915, 1014, 1179, 1299, 1496, 1649, 1892, 2078, 2368, 2597, 2953, 3230, 3645, 3986, 4492, 4895
OFFSET
0,13
FORMULA
a(n) = Sum_{r=1..floor(n/10)} Sum_{q=r..floor((n-r)/9)} Sum_{p=q..floor((n-q-r)/8)} Sum_{o=p..floor((n-p-q-r)/7)} Sum_{m=o..floor((n-o-p-q-r)/6)} Sum_{l=m..floor((n-m-o-p-q-r)/5)} Sum_{k=l..floor((n-l-m-o-p-q-r)/4)} Sum_{j=k..floor((n-k-l-m-o-p-q-r)/3)} Sum_{i=j..floor((n-j-k-l-m-o-p-q-r)/2)} mu(r)^2 * mu(q)^2 * mu(p)^2 * mu(o)^2 * mu(m)^2 * mu(l)^2 * mu(k)^2 * mu(j)^2 * mu(i)^2 * mu(n-i-j-k-l-m-o-p-q-r)^2, where mu is the Möbius function (A008683).
a(n) = A326627(n)/n for n > 0.
MATHEMATICA
Table[Count[IntegerPartitions[n, {10}], _?(AllTrue[#, SquareFreeQ]&)], {n, 0, 60}] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Aug 25 2019 *)
KEYWORD
nonn
AUTHOR
Wesley Ivan Hurt, Jul 14 2019
STATUS
approved