Column of Motzkin triangle A026300.

Terms

a(0) =1a(1) =5a(2) =20a(3) =70a(4) =230a(5) =726a(6) =2235a(7) =6765a(8) =20240a(9) =60060a(10) =177177a(11) =520455a(12) =1524120a(13) =4453320a(14) =12991230a(15) =37854954a(16) =110218905a(17) =320751445a(18) =933149470a(19) =2714401580a(20) =7895719634a(21) =22969224850a(22) =66829893650a(23) =194486929650a(24) =566141346225