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A174282 a(n) = 3^n mod M(n) where M(n) = A014963(n) is the exponential of the Mangoldt function. 1

%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^(n-1) , 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

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Last modified January 22 15:57 EST 2019. Contains 319364 sequences. (Running on oeis4.)