a(n) = numerator(hypergeom([-n, 1/2], [1], 1)*hypergeom([-floor(n/2), (-1)^n/2], [1], 1)).

A295871

a(n) = numerator(hypergeom([-n, 1/2], [1], 1)*hypergeom([-floor(n/2), (-1)^n/2], [1], 1)).

Terms

    a(0) =1a(1) =1a(2) =3a(3) =15a(4) =105a(5) =945a(6) =1155a(7) =15015a(8) =225225a(9) =3828825a(10) =2909907a(11) =61108047a(12) =156165009a(13) =3904125225a(14) =2151252675a(15) =62386327575

External references