a(n) = Sum_{k=1..n} floor(k^4/n).

Terms

a(0) =1a(1) =8a(2) =32a(3) =88a(4) =195a(5) =377a(6) =666a(7) =1096a(8) =1701a(9) =2530a(10) =3630a(11) =5056a(12) =6863a(13) =9115a(14) =11884a(15) =15240a(16) =19249a(17) =24012a(18) =29606a(19) =36126a(20) =43665a(21) =52327a(22) =62220a(23) =73452a(24) =86137a(25) =100398a(26) =116364a(27) =134158a(28) =153915a(29) =175789