a(n) = floor(n^2 / e).

Terms

a(0) =0a(1) =0a(2) =1a(3) =3a(4) =5a(5) =9a(6) =13a(7) =18a(8) =23a(9) =29a(10) =36a(11) =44a(12) =52a(13) =62a(14) =72a(15) =82a(16) =94a(17) =106a(18) =119a(19) =132a(20) =147a(21) =162a(22) =178a(23) =194a(24) =211a(25) =229a(26) =248a(27) =268a(28) =288a(29) =309