Main diagonal of A332369.

Terms

a(0) =3a(1) =9a(2) =35a(3) =77a(4) =191a(5) =321a(6) =591a(7) =941a(8) =1503a(9) =2097a(10) =3047a(11) =4173a(12) =5835a(13) =7577a(14) =9815a(15) =12341a(16) =15763a(17) =19361a(18) =24083a(19) =29317a(20) =35615a(21) =42041a(22) =50095a(23) =58853a(24) =69395a(25) =80129a(26) =92675a(27) =106133a(28) =122239a(29) =138969