a(n)=least number m such that m-a(n-1)<>a(j)-a(k) for all j,k less than m; a(1)=1, a(2)=3.

Terms

a(0) =1a(1) =3a(2) =4a(3) =8a(4) =14a(5) =22a(6) =31a(7) =43a(8) =58a(9) =74a(10) =94a(11) =116a(12) =140a(13) =165a(14) =191a(15) =223a(16) =256a(17) =290a(18) =327a(19) =365a(20) =406a(21) =451a(22) =498a(23) =546a(24) =599a(25) =655a(26) =714a(27) =775a(28) =837a(29) =901