A068001 - OEIS

%I #14 Apr 28 2019 05:38:14

%S 1,5,7,8,9,2,5,13,46,2,19,15,6,74,12,58,4,8,5,52,6,128,85,53,15,61,

%T 113,17,55,52,83,47,147,43,297,238,63,117,51,49,145,98,219,109,48,38,

%U 114,283,423,226,334,168,38,87,91,58,189,166,42,222,92,59,133,86,544,264,5

%N Smallest number whose n-th power (A067457) starts with n.

%H Paolo P. Lava, <a href="/A068001/b068001.txt">Table of n, a(n) for n = 1..500</a>

%e a(3) = 7 because 7^3 = 343 which starts with 3 and there is no number less than 7 with this property.

%t Do[k = Floor[ Log[ 10, n] + 1]; While[ FromDigits[ Take[ IntegerDigits [k^n], Floor[ Log[ 10, n] + 1]]] != n, k++ ]; Print[k^n], {n, 1, 100} ]

%Y Cf. A051248, A067457.

%K base,easy,nonn

%O 1,2

%A _Robert G. Wilson v_, Feb 08 2002