OFFSET
1,2
COMMENTS
LINKS
Georg Fischer, Table of n, a(n) for n = 1..300 [First 152 terms by Vincenzo Librandi]
FORMULA
a(n) = ceiling((10^n)^(1/5)) - 1.
EXAMPLE
a(3) = 3 because 3^5 = 243 which has 3 digits, while 4^5 = 1024 has 3 digits.
a(32) = 2511886 because 2511886^5 = 99999914106500508412371346814176 has 32 digits, while 2511887^5 = 100000113160107495177704749808207 has 33 digits.
MAPLE
seq(print(n, floor((10^n-1)^(1/5))), n=1..300); # Georg Fischer Apr 17 2024
MATHEMATICA
Table[Floor[(10^n-1)^(1/5)], {n, 40}] (* Harvey P. Dale, Dec 10 2012 *)
PROG
(PARI) a(n) = sqrtnint(10^n-1, 5) /* Georg Fischer on proposal of Michel Marcus, Apr 16 2024 */
(Magma) [Ceiling((10^n)^(1/5))-1: n in [1..40]]; // Vincenzo Librandi, Oct 11 2011
CROSSREFS
KEYWORD
easy,nonn,base
AUTHOR
Jonathan Vos Post, Feb 06 2006
EXTENSIONS
Data corrected by Vincenzo Librandi, Oct 11 2011
STATUS
approved