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%I #14 Jul 01 2022 03:30:09
%S 1,2,7,34,208,1521,12871,123306,1316316,15471114,198319614,2751524557,
%T 41058030388,655427422651,11142214939181,200919300509214,
%U 3829751956014084,76928721540858772,1624015067086462504,35942784684670110710,832134062464902004336
%N a(n) = Sum_{k=1..n} |Stirling1(n,k)| * Catalan(k-1).
%t Table[Sum[Abs[StirlingS1[n,k]] * CatalanNumber[k-1], {k,1,n}], {n,1,20}] (* _Vaclav Kotesovec_, Jul 01 2022 *)
%o (PARI) a(n) = sum(k=1, n, abs(stirling(n, k, 1))*binomial(2*k-2, k-1)/k);
%Y Cf. A000108, A052851, A086662.
%K nonn
%O 1,2
%A _Seiichi Manyama_, Jun 27 2022
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