Number of n-digit 4th powers.

Terms

a(0) =2a(1) =2a(2) =2a(3) =4a(4) =8a(5) =14a(6) =25a(7) =43a(8) =78a(9) =139a(10) =246a(11) =437a(12) =779a(13) =1384a(14) =2461a(15) =4376a(16) =7783a(17) =13840a(18) =24612a(19) =43765a(20) =77828a(21) =138400a(22) =246114a(23) =437658a(24) =778280a(25) =1383998a(26) =2461136a(27) =4376586a(28) =7782795a(29) =13839982