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A136275 Similar to A137284, but considering Sum{ k = 1,2,3,... } 5^(-nk). 1
1, 2, 3, 5, 8, 12, 18, 26, 38, 55, 79, 114, 164, 235, 337, 483, 692, 991, 1418, 2029, 2903, 4154, 5944, 8504, 12167, 17408, 24906, 35633, 50980, 72936, 104348, 149289, 213585, 305572, 437175, 625457, 894827, 1280209, 1831566, 2620379, 3748915 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

FORMULA

a(n) = ceiling( a(n-1)*log_5(10) ). - Max Alekseyev, May 14 2009

EXAMPLE

Start from 0;

0 + 5^(-1) = 0.2;

0.2 + 5^(-2) = 0.24 (first digit "2" is equal to the previous number's digit after the decimal point);

0.24 + 5^(-3) = 0.248 (first digits "24" are equal to the previous number's digits after the decimal point);

0.248 + 5^(-5) = 0.24832 (first digits "248" are equal to the previous number's digits after the decimal point);

etc.

MATHEMATICA

Join[{1}, a=1; a=Table[a=Ceiling[a Log[5, 10]], {n, 40}]] (* Vincenzo Librandi, Jul 05 2019 *)

PROG

(MAGMA) [n eq 1 select 1 else Ceiling(Self(n-1)*Log(5, 10)): n in [1..50]]; // Vincenzo Librandi, Jul 05 2019

CROSSREFS

Sequence in context: A328085 A001524 A280278 * A344002 A328170 A078408

Adjacent sequences:  A136272 A136273 A136274 * A136276 A136277 A136278

KEYWORD

nonn,base,easy

AUTHOR

Paolo P. Lava and Giorgio Balzarotti, Mar 19 2008

EXTENSIONS

Extended by Max Alekseyev, May 14 2009

STATUS

approved

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Last modified May 26 10:17 EDT 2022. Contains 354086 sequences. (Running on oeis4.)