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%I #26 Sep 08 2022 08:45:29
%S 1,2,4,8,16,32,64,128,256,512,24,48,96,192,384,768,536,72,144,288,576,
%T 152,304,608,216,432,864,728,456,912,824,648,296,592,184,368,736,472,
%U 944,888,776,552,104,208,416,832,664,328,656,312,624,248,496,992,984,968
%N Final three digits of 2^n.
%C Has period 100. Sequence of last four digits has period 500. Cf. A000855 Final two digits of 2^n, has period 20.
%H V. Raman and Vincenzo Librandi, <a href="/A126605/b126605.txt">Table of n, a(n) for n = 0..1000</a> (first 103 terms from V. Raman)
%t Table[PowerMod[2,n,1000],{n,1000}]
%o (PARI) for(i=1,103,print(i" "(2^i)%1000)) \\ _V. Raman_, Sep 01 2012
%o (Magma) [Modexp(2, n, 1000): n in [0..110]]; // _Vincenzo Librandi_, Aug 16 2016
%Y Cf. A000689, A000855.
%K nonn,base,easy
%O 0,2
%A _Zak Seidov_, Mar 13 2007