a(n) = 63*((10^n - 1)/9)^2.A178634a(n) = 63*((10^n - 1)/9)^2.Terms a(0) =63a(1) =7623a(2) =776223a(3) =77762223a(4) =7777622223a(5) =777776222223External referencesoeis: A178634