Coefficient of x^n in the expansion of ( (1+x) * (1+x+x^2)^2 )^n.

A370159

Coefficient of x^n in the expansion of ( (1+x) * (1+x+x^2)^2 )^n.

Terms

    a(0) =1a(1) =3a(2) =19a(3) =132a(4) =963a(5) =7228a(6) =55264a(7) =428067a(8) =3347843a(9) =26378079a(10) =209065644a(11) =1664967747a(12) =13312423056a(13) =106798422942a(14) =859244421187

External references