a(n) = (4*10^n + 23)/9.

A173772

a(n) = (4*10^n + 23)/9.

Terms

    a(0) =7a(1) =47a(2) =447a(3) =4447a(4) =44447a(5) =444447a(6) =4444447a(7) =44444447a(8) =444444447a(9) =4444444447a(10) =44444444447a(11) =444444444447

External references