A174282 - OEIS

A174282

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

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, 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, 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

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Appears to be always either 0 or 1.

This follows from Fermat's Little Theorem. - Charles R Greathouse IV, Feb 13 2011

LINKS

G. C. Greubel, Table of n, a(n) for n = 1..1000

FORMULA

a(n) = A000244(n) mod A014963(n).

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

MATHEMATICA

f[n_] := PowerMod[3, n - 1, Exp@ MangoldtLambda@ n]; Array[f, 105] (* Robert G. Wilson v, Jan 22 2015 *)

Table[mod[3^(n-1) , e^(MangoldtLambda[n]) ], {n, 1, 100}] (* G. C. Greubel, Nov 25 2015 *)

PROG

(PARI) vector(95, n, ispower(k=n, , &k); isprime(k)&k!=3) \\ Charles R Greathouse IV, Feb 13 2011

CROSSREFS

Cf. A174275, A062174.

Sequence in context: A334820 A308185 A159689 * A189301 A123640 A022924

Adjacent sequences: A174279 A174280 A174281 * A174283 A174284 A174285

KEYWORD

nonn,easy

AUTHOR

Mats Granvik, Mar 15 2010

EXTENSIONS

More terms from Robert G. Wilson v, Jan 22 2015

STATUS

approved