a(n) = Sum_{k=0..n} binomial(2*n, n-k) * q(k), where q(k) is the number of partitions into distinct parts (A000009).

A356281

a(n) = Sum_{k=0..n} binomial(2*n, n-k) * q(k), where q(k) is the number of partitions into distinct parts (A000009).

Terms

    a(0) =1a(1) =3a(2) =11a(3) =43a(4) =172a(5) =695a(6) =2823a(7) =11501a(8) =46940a(9) =191791a(10) =784148a(11) =3207196a(12) =13119733a(13) =53670793a(14) =219545353a(15) =897957702a(16) =3672093558a(17) =15013596535a(18) =61370565546a(19) =250803861369

External references