Convolution of composite numbers and odd numbers.

Terms

a(0) =4a(1) =18a(2) =46a(3) =91a(4) =155a(5) =241a(6) =353a(7) =494a(8) =666a(9) =872a(10) =1116a(11) =1401a(12) =1729a(13) =2103a(14) =2526a(15) =3000a(16) =3527a(17) =4109a(18) =4749a(19) =5451a(20) =6218a(21) =7052a(22) =7955a(23) =8929a(24) =9977a(25) =11102a(26) =12306a(27) =13592a(28) =14964a(29) =16425