%I
%S 0,1,0,1,1,0,1,1,0,0,1,0,1,0,0,1,1,0,1,0,0,0,1,0,1,0,0,0,1,0,1,1,0,0,
%T 0,0,1,0,0,0,1,0,1,0,0,0,1,0,1,0,0,0,1,0,0,0,0,0,1,0,1,0,0,1,0,0,1,0,
%U 0,0,1,0,1,0,0,0,0,0,1,0,0,0,1,0,0,0,0,0,1,0,0,0,0,0,0,0,1,0,0,0,1,0,1,0,0
%N a(n) = 3^n mod M(n) where M(n) = A014963(n) is the exponential of the Mangoldt function.
%C Appears to be always either 0 or 1.
%C This follows from Fermat's Little Theorem.  _Charles R Greathouse IV_, Feb 13 2011
%H G. C. Greubel, <a href="/A174282/b174282.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = A000244(n) mod A014963(n).
%F a(n) = 1 if n = p^k for k > 0 and p a prime not equal to 3, a(n) = 0 otherwise.  _Charles R Greathouse IV_, Feb 13 2011
%t f[n_] := PowerMod[3, n  1, Exp@ MangoldtLambda@ n]; Array[f, 105] (* _Robert G. Wilson v_, Jan 22 2015 *)
%t Table[mod[3^(n1) , e^(MangoldtLambda[n]) ], {n, 1, 100}] (* _G. C. Greubel_, Nov 25 2015 *)
%o (PARI) vector(95,n,ispower(k=n,,&k);isprime(k)&k!=3) \\ _Charles R Greathouse IV_, Feb 13 2011
%Y Cf. A174275, A062174.
%K nonn,easy
%O 1,1
%A _Mats Granvik_, Mar 15 2010
%E More terms from _Robert G. Wilson v_, Jan 22 2015
