a(n) = floor(1000/sqrt(n)).

Terms

a(0) =1000a(1) =707a(2) =577a(3) =500a(4) =447a(5) =408a(6) =377a(7) =353a(8) =333a(9) =316a(10) =301a(11) =288a(12) =277a(13) =267a(14) =258a(15) =250a(16) =242a(17) =235a(18) =229a(19) =223a(20) =218a(21) =213a(22) =208a(23) =204a(24) =200a(25) =196a(26) =192a(27) =188a(28) =185a(29) =182