Matrix square of Stirling-1 triangle A008275.

Terms

a(0) =1a(1) =-2a(2) =1a(3) =7a(4) =-6a(5) =1a(6) =-35a(7) =40a(8) =-12a(9) =1a(10) =228a(11) =-315a(12) =130a(13) =-20a(14) =1a(15) =-1834a(16) =2908a(17) =-1485a(18) =320a(19) =-30a(20) =1a(21) =17582a(22) =-30989a(23) =18508a(24) =-5005a(25) =665a(26) =-42a(27) =1a(28) =-195866a(29) =375611