p-INVERT of (1,1,0,0,0,0,...), where p(S) = 1 - 3 S + S^2 + S^3.

Terms

a(0) =3a(1) =11a(2) =36a(3) =117a(4) =375a(5) =1197a(6) =3810a(7) =12112a(8) =38478a(9) =122198a(10) =388008a(11) =1231911a(12) =3911097a(13) =12416751a(14) =39419610a(15) =125145175a(16) =397296363a(17) =1261288403a(18) =4004182620a(19) =12711979296a(20) =40356397332a(21) =128118414852a(22) =406734209280