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Convolution of number of overpartitions and Catalan numbers.
0

%I #5 Sep 20 2017 10:20:29

%S 1,3,8,21,54,144,404,1195,3712,12000,39994,136400,473430,1665868,

%T 5926476,21275805,76964808,280250088,1026309908,3777411342,

%U 13965286180,51837285776,193107846304,721732334136,2705480787422,10169387310362,38320472420462,144733083435688

%N Convolution of number of overpartitions and Catalan numbers.

%F a(n) ~ c * 4^n / (sqrt(Pi) * n^(3/2)), where c = QPochhammer[-1, 1/4] / (2*QPochhammer[1/4, 1/4]) = 1.96926035366826943194719369696726567...

%t Table[Sum[Sum[PartitionsP[k-j] * PartitionsQ[j], {j, 0, k}] * CatalanNumber[n-k], {k, 0, n}], {n, 0, 50}]

%Y Cf. A000108, A015128, A014329, A292617.

%K nonn

%O 0,2

%A _Vaclav Kotesovec_, Sep 20 2017