Column 0 of triangle A115085.

Terms

a(0) =1a(1) =1a(2) =3a(3) =12a(4) =58a(5) =321a(6) =1963a(7) =13053a(8) =92946a(9) =702864a(10) =5599204a(11) =46746501a(12) =407019340a(13) =3682922657a(14) =34519445611a(15) =334288656446