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A205770
Powers of fifth root of 100, rounded to the nearest integer.
1
1, 3, 6, 16, 40, 100, 251, 631, 1585, 3981, 10000, 25119, 63096, 158489, 398107, 1000000, 2511886, 6309573, 15848932, 39810717, 100000000, 251188643, 630957344, 1584893192, 3981071706, 10000000000, 25118864315, 63095734448, 158489319246, 398107170553, 1000000000000
OFFSET
0,2
COMMENTS
The fifth root of 100, known as Pogson's ratio, is the ratio between successive stellar magnitudes.
LINKS
Eric Weisstein's World of Mathematics, Pogson's Ratio
MATHEMATICA
Table[Round[100^(n/5)], {n, 0, 30}] (* G. C. Greubel, Jan 14 2018 *)
PROG
(PARI) a(n)=round(100^(n/5)) \\ Charles R Greathouse IV, Jan 31 2012
(Python)
from gmpy2 import iroot
def A205770(n):
m = 100**n
i = iroot(m, 5)[0]
return int(i) + int(32*m >= (1+2*i)**5) # Chai Wah Wu, Aug 16 2016
(Magma) [Round(100^(n/5)): n in [0..30]]; // G. C. Greubel, Jan 14 2018
CROSSREFS
Bisection of A018142, ratio is A189824.
Sequence in context: A188442 A046211 A239980 * A301959 A018022 A166536
KEYWORD
nonn,easy
AUTHOR
STATUS
approved