A001264 Final 2 digits of 4^n.

1, 4, 16, 64, 56, 24, 96, 84, 36, 44, 76, 4, 16, 64, 56, 24, 96, 84, 36, 44, 76, 4, 16, 64, 56, 24, 96, 84, 36, 44, 76, 4, 16, 64, 56, 24, 96, 84, 36, 44, 76, 4, 16, 64, 56, 24, 96, 84, 36, 44, 76, 4, 16, 64, 56, 24, 96

Offset

0,2

Comments

The period is 10: for n > 0, a(n) = a(n + 10).

Links

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

Index entries for sequences related to final digits of numbers

Index entries for linear recurrences with constant coefficients, signature (1,0,0,0,-1,1).

Maple

seq(4^n mod 10^2, n=0..60); # Martin Renner, Jan 25 2017

Mathematica

PowerMod[4, Range[0, 60], 100] (* Vincenzo Librandi, Aug 15 2016 *)

Prog

(Magma) [Modexp(4, n, 100): n in [0..110]]; // Vincenzo Librandi, Aug 15 2016
(PARI) a(n)=lift(Mod(4, 100)^n) \\ Charles R Greathouse IV, Jan 25 2017

Crossrefs

Sequence in context: A061283 A375976 A242354 * A307138 A114399 A029993

Adjacent sequences: A001261 A001262 A001263 * A001265 A001266 A001267

Keyword

nonn,easy

Author

N. J. A. Sloane

Status

approved