A symmetrical triangle of coefficients based on A001147: a(n)=(2*n-1)*a(n-1); t(n,m)=a(n)^2/((2*n - 1)*a(m)*a(n - m)).

A143081

A symmetrical triangle of coefficients based on A001147: a(n)=(2*n-1)*a(n-1); t(n,m)=a(n)^2/((2*n - 1)*a(m)*a(n - m)).

Terms

    a(0) =-1a(1) =1a(2) =1a(3) =1a(4) =3a(5) =1a(6) =3a(7) =15a(8) =15a(9) =3a(10) =15a(11) =105a(12) =175a(13) =105a(14) =15a(15) =105a(16) =945a(17) =2205a(18) =2205a(19) =945a(20) =105a(21) =945a(22) =10395a(23) =31185a(24) =43659a(25) =31185a(26) =10395a(27) =945a(28) =10395a(29) =135135

External references