Convolution of natural numbers (A000027) with tetradecagonal numbers (A051866).

Terms

a(0) =0a(1) =1a(2) =16a(3) =70a(4) =200a(5) =455a(6) =896a(7) =1596a(8) =2640a(9) =4125a(10) =6160a(11) =8866a(12) =12376a(13) =16835a(14) =22400a(15) =29240a(16) =37536a(17) =47481a(18) =59280a(19) =73150a(20) =89320a(21) =108031a(22) =129536a(23) =154100a(24) =182000a(25) =213525a(26) =248976a(27) =288666a(28) =332920a(29) =382075