a(n) = Sum_{k=0..n} (-1)^k*A001595(k)^2.

Terms

a(0) =1a(1) =0a(2) =9a(3) =-16a(4) =65a(5) =-160a(6) =465a(7) =-1216a(8) =3273a(9) =-8608a(10) =22721a(11) =-59648a(12) =156577a(13) =-410432a(14) =1075529a(15) =-2817200a(16) =7378049a(17) =-19319840a(18) =50586481a(19) =-132447360a(20) =346768521a(21) =-907878720a(22) =2376901249a(23) =-6222878976a(24) =16291823425a(25) =-42652732800a(26) =111666604425a(27) =-292347451216a(28) =765376349633