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%I #14 Apr 21 2021 17:34:08
%S 1,256,387420489,4096,59604644775390625,60466176,79792266297612001,
%T 8589934592,984770902183611232881,100,121,144,169,196,11390625,
%U 1048576,1419857,104976,130321,25600000000,278218429446951548637196401
%N Least n^k with same leading decimal digit as n, k>1.
%H Robert Israel, <a href="/A073600/b073600.txt">Table of n, a(n) for n = 1..5995</a>
%F a(n) = n^A073601(n);
%F A000030(a(n)) = A000030(n).
%e a(4)=4096, as 4096=4^6 is the least power of 4 with initial digit =4: 4^2=16, 4^3=64, 4^4=256 and 4^5=1024; A073601(4)=6.
%p f:= proc(n) local t,k,m;
%p t:= floor(n/10^ilog10(n));
%p for k from 2 do
%p m:= n^k;
%p if floor(m/10^ilog10(m)) = t then return m fi
%p od
%p end proc:
%p map(f, [$1..100]); # _Robert Israel_, Apr 21 2021
%t fi[n_] := First[IntegerDigits[n]]; Table[k = 2; While[fi[x = n^k] != fi[n], k++]; x, {n, 21}] (* _Jayanta Basu_, Jul 02 2013 *)
%K nonn,base,look
%O 1,2
%A _Reinhard Zumkeller_, Aug 04 2002
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