The cube of the g.f. equals the g.f. of A196306.

Terms

a(0) =1a(1) =1a(2) =-1a(3) =2a(4) =-4a(5) =9a(6) =-22a(7) =55a(8) =-142a(9) =375a(10) =-1009a(11) =2753a(12) =-7599a(13) =21178a(14) =-59509a(15) =168401a(16) =-479477a(17) =1372536a(18) =-3947678a(19) =11402376a(20) =-33059314a(21) =96177750a(22) =-280671373a(23) =821379083a(24) =-2409938978a(25) =7087502564a(26) =-20889306810a(27) =61691675424a(28) =-182531101523a(29) =541000651928