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Smallest number whose cube ends in n, or 0 if no such number exists. a(n) = A077743(n)^(1/3).
3

%I #13 Mar 06 2023 02:55:00

%S 1,8,7,4,5,6,3,2,9,0,71,8,17,0,0,6,73,0,39,0,41,0,47,24,5,0,3,12,9,0,

%T 11,18,77,0,0,46,33,0,79,0,81,0,7,14,0,0,63,22,49,0,51,28,37,0,0,36,

%U 93,0,19,0,21,0,67,4,0,0,23,32,89,0,91,38,97,0,15,26,53,0,59,0,61,0,27,44,0

%N Smallest number whose cube ends in n, or 0 if no such number exists. a(n) = A077743(n)^(1/3).

%H Robert Israel, <a href="/A077744/b077744.txt">Table of n, a(n) for n = 1..10000</a>

%F a(m*10^(3k+1)) = a(m*10^(3k+2) = 0.

%e a(13) = 17, a(10) = 0.

%p f:= proc(n) local m,r,x;

%p m:= 10^(ilog10(n)+1);

%p r:= [msolve(x^3=n,m)];

%p if r = [] then 0 else min(map(t -> rhs(op(t)),r)) fi

%p end proc:

%p map(f, [$1..100]); # _Robert Israel_, Mar 05 2023

%Y Cf. A000578, A077743, A246449.

%K base,nonn

%O 1,2

%A _Amarnath Murthy_, Nov 20 2002

%E More terms from _Sascha Kurz_, Jan 07 2003