A032543 Numbers that, when expressed in base 5 and then interpreted in base 10, yield a multiple of the original number.
0, 1, 2, 3, 4, 5, 10, 15, 20, 25, 50, 75, 100, 125, 160, 224, 237, 250, 320, 330, 375, 490, 500, 625, 800, 1000, 1120, 1185, 1250, 1600, 1650, 1875, 2450, 2500, 3125, 3800, 4000, 4704, 5000, 5600, 5925, 6250, 7600, 8000, 8250, 9375, 10000, 12250
Offset: 1
Examples
25 in base 5 is 100, which interpreted in base 10 is 100 = 4 * 25. 224 in base 5 is 1344, which interpreted in base 10 is 1344 = 6 * 224.
Links
- Giovanni Resta, Table of n, a(n) for n = 1..577 (terms < 5*10^12, first 147 terms from Robert Israel)
Programs
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Maple
filter:= proc(n) local L,i; L:= convert(n,base,5); add(L[i]*10^(i-1),i=1..nops(L)) mod n = 0 end proc: 0, op(select(filter, [$1..10^5])); # Robert Israel, Apr 10 2016
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Mathematica
Select[Range[0,13000], Divisible[FromDigits[IntegerDigits[#, 5]], #] &] (* Harvey P. Dale, Feb 01 2011 *)
Extensions
Example and better description from Erich Friedman, Jul 21 2001
Edited by Erich Friedman, Feb 09 2002
Offset changed and 0 inserted by Robert Israel, Apr 11 2016
Name edited by Jon E. Schoenfield, Oct 25 2019
Comments