OFFSET
1,2
FORMULA
a(n) = Min( 5^(2^n) (mod 10^n), 16^(5^n) (mod 10^n) ). - Robert G. Wilson v, Aug 27 2006
MATHEMATICA
f[n_] := If[n == 1, 0, Block[{a5 = PowerMod[5, 2^n, 10^n], a6 = PowerMod[16, 5^n, 10^n]}, If[a5 < 10^(n - 1), a5 = 10^(n + 1)]; If[a6 < 10^(n - 1), a6 = 10^(n + 1)]; Min[a5, a6]]]; Array[f, 19] (* Robert G. Wilson v, Aug 27 2006 *)
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Lekraj Beedassy, May 25 2004
EXTENSIONS
Corrected and extended by Robert G. Wilson v, Aug 27 2006
STATUS
approved