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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

The fifth root of 100, known as Pogson's ratio, is the ratio between successive stellar magnitudes.

LINKS

Chai Wah Wu, Table of n, a(n) for n = 0..1000

Eric Weisstein's World of Mathematics, Pogson's Ratio

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

CROSSREFS

Bisection of A018142, ratio is A189824.

Sequence in context: A188442 A046211 A239980 * A018022 A166536 A128720

Adjacent sequences:  A205767 A205768 A205769 * A205771 A205772 A205773

KEYWORD

nonn,easy

AUTHOR

Franklin T. Adams-Watters, Jan 31 2012

STATUS

approved

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Last modified December 10 23:13 EST 2016. Contains 279021 sequences.