a(n) = (36^n - 1)/35.A218739a(n) = (36^n - 1)/35.Terms a(0) =0a(1) =1a(2) =37a(3) =1333a(4) =47989a(5) =1727605a(6) =62193781a(7) =2238976117a(8) =80603140213External referencesoeis: A218739