Set x=3 in polynomial corresponding to A253091(n).

Terms

a(0) =1a(1) =7a(2) =13a(3) =55a(4) =142a(5) =715a(6) =757a(7) =5299a(8) =9841a(9) =39367a(10) =98422a(11) =511771a(12) =570862a(13) =3818644a(14) =7421206a(15) =29800819a(16) =74505454a(17) =387410647a(18) =387440173a(19) =2712081211a(20) =5036722249a(21) =21309209515a(22) =55016504566a(23) =277019723695a(24) =293292210961