Partial sum of Perrin numbers.

Terms

a(0) =3a(1) =3a(2) =5a(3) =8a(4) =10a(5) =15a(6) =20a(7) =27a(8) =37a(9) =49a(10) =66a(11) =88a(12) =117a(13) =156a(14) =207a(15) =275a(16) =365a(17) =484a(18) =642a(19) =851a(20) =1128a(21) =1495a(22) =1981a(23) =2625a(24) =3478a(25) =4608a(26) =6105a(27) =8088a(28) =10715a(29) =14195