Ordered Stirling numbers S1(n,k) >= 0.

Terms

a(0) =0a(1) =1a(2) =2a(3) =11a(4) =24a(5) =35a(6) =85a(7) =175a(8) =274a(9) =322a(10) =546a(11) =720a(12) =870a(13) =1320a(14) =1624a(15) =1925a(16) =2717a(17) =3731a(18) =5005a(19) =6580a(20) =6769a(21) =8500a(22) =10812a(23) =13068a(24) =13566a(25) =16815a(26) =20615a(27) =22449a(28) =25025a(29) =30107