Column 5 of triangle A055898.

Terms

a(0) =1a(1) =11a(2) =76a(3) =376a(4) =1496a(5) =5032a(6) =14872a(7) =39572a(8) =96607a(9) =219373a(10) =468440a(11) =948640a(12) =1834560a(13) =3407040a(14) =6104736a(15) =10594728a(16) =17868213a(17) =29367063a(18) =47149828a(19) =74105240a(20) =114224968a(21) =172946488a(22) =257581688a(23) =377845468a(24) =546504595a(25) =780165113