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%I #10 Jan 01 2024 19:05:18
%S 1,2,3,4,5,6,7,8,9,25,32,36,64,125,216,243,512,625,729,1024,1296,3125,
%T 7776,8192,15625,16384,16807,19683,32768,46656,59049,78125,131072,
%U 262144,279936,390625,1594323,1679616,1953125,2097152,4194304,4782969
%N Positive numbers which are powers of their last digit.
%C Subsequence of A100753.
%C 1, 5^k or 6^k for all k, 4^k or 9^k for all odd k, 2^k or 3^k or 7^k or 8^k for all k == 1 (mod 4). - _Robert Israel_, Apr 25 2017
%H Robert Israel, <a href="/A132416/b132416.txt">Table of n, a(n) for n = 1..5993</a>
%e 9=9^1, 25=5^2, 32=2^5, 36=6^2, 64=4^3, 125=5^3, 216=6^3, 243=3^5, 512=2^9, 625=5^4, etc.
%p N:= 10^9: # to get all terms <= N
%p S:= {1, seq(2^k,k=1..ilog2(N),4), seq(3^k,k=1..floor(log[3](N)),4),
%p seq(4^k,k=1..floor(log[4](N)),2), seq(5^k,k=1..floor(log[5](N))),
%p seq(6^k,k=1..floor(log[6](N))), seq(7^k,k=1..floor(log[7](N)),4),
%p seq(8^k,k=1..floor(log[8](N)),4),seq(9^k,k=1..floor(log[9](N)),2)}:
%p sort(convert(S,list)); # _Robert Israel_, Apr 25 2017
%t pldQ[n_]:=Module[{idn=IntegerDigits[n],lst},lst=Last[idn];lst>1&& IntegerQ[ Log[ lst,n]]]; Join[{1},Select[Range[5*10^6],pldQ]] (* _Harvey P. Dale_, Jul 26 2014 *)
%Y Cf. A100753.
%K base,nonn
%O 1,2
%A _Zak Seidov_, Nov 13 2007
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