Second-order Lucas numbers; a(n) = (2n+3)*Lucas(n) - n*Lucas(n-1).

Terms

a(0) =6a(1) =3a(2) =19a(3) =27a(4) =61a(5) =108a(6) =204a(7) =367a(8) =661a(9) =1173a(10) =2069a(11) =3622a(12) =6306a(13) =10923a(14) =18839a(15) =32367a(16) =55421a(17) =94608a(18) =161064a(19) =273527a(20) =463481a(21) =783753a(22) =1322869a(23) =2229002a(24) =3749886a(25) =6299283a(26) =10567579a(27) =17705667a(28) =29630461a(29) =49532148