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A014329
Convolution of partition numbers and Catalan numbers.
6
1, 2, 5, 12, 31, 84, 245, 752, 2413, 7991, 27104, 93605, 327886, 1161735, 4155323, 14982399, 54393829, 198666117, 729443563, 2690890444, 9968312790, 37066929338, 138304185107, 517646986719, 1942966098461, 7311862919106, 27582428518833, 104279585166245
OFFSET
0,2
LINKS
FORMULA
a(n) ~ c * 4^n / (sqrt(Pi) * n^(3/2)), where c = Sum_{k>=0} A000041(k)/4^k = 1/QPochhammer[1/4, 1/4] = 1.4523536424495970158347130224852748733612279788... . - Vaclav Kotesovec, Jun 23 2015
G.f.: (1 - sqrt(1-4*x))/(2*x*QPochhammer(x)). - G. C. Greubel, Jan 08 2023
MATHEMATICA
Table[Sum[PartitionsP[k]*CatalanNumber[n-k], {k, 0, n}], {n, 0, 50}] (* Vaclav Kotesovec, Jun 23 2015 *)
PROG
(Magma)
A000041:= func< n | NumberOfPartitions(n) >;
A014329:= func< n | (&+[A000041(j)*Catalan(n-j): j in [0..n]]) >;
[A014329(n): n in [0..40]]; // G. C. Greubel, Jan 08 2023
(SageMath)
def A000041(n): return number_of_partitions(n)
def A014329(n): return sum(A000041(j)*catalan_number(n-j) for j in range(n+1))
[A014329(n) for n in range(41)] # G. C. Greubel, Jan 08 2023
CROSSREFS
KEYWORD
nonn
STATUS
approved