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A034082
a(n) = least integer m such that the part after the decimal point of the n-th root of m starts with the digit 5.
6
21, 4, 6, 8, 12, 18, 26, 39, 58, 87, 130, 195, 292, 438, 657, 986, 1478, 2217, 3326, 4988, 7482, 11223, 16835, 25252, 37877, 56816, 85223, 127835, 191752, 287627, 431440, 647160, 970740, 1456110, 2184165, 3276247, 4914370, 7371555, 11057333
OFFSET
2,1
FORMULA
For n > 2: a(n) = ceiling((3/2)^n) = A002379(n) + 1. - Henry Bottomley, May 02 2001
EXAMPLE
a(25)=25252 -> 25252^(1/25)=1.{5}000019762083...
PROG
(Python)
def A034082(n): return (3**n>>n)+1 if n > 2 else 21 # Chai Wah Wu, Sep 21 2022
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, Sep 15 1998
EXTENSIONS
Definition clarified by N. J. A. Sloane, May 24 2021
STATUS
approved