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Even numbers k such that (k^3+1)/(k+1) is prime.
8

%I #13 Sep 18 2022 10:05:37

%S 2,4,6,16,18,22,28,34,42,58,60,70,72,76,78,90,100,102,106,112,118,120,

%T 132,142,144,148,154,156,162,168,174,190,204,210,216,232,246,280,288,

%U 294,310,330,352,358,370,382,384,396,406,436,448,454,456,490,496,526

%N Even numbers k such that (k^3+1)/(k+1) is prime.

%H Hugo Pfoertner, <a href="/A096174/b096174.txt">Table of n, a(n) for n = 1..10000</a>

%e a(1)=2 because (2^3+1)/(2+1)=9/3=3 is prime, a(8)=34: (34^3+1)/(34+1)=39305/35=1123 is prime.

%o (PARI) is(n)=n%2==0 && isprime((n^3+1)/(n+1)) \\ _Charles R Greathouse IV_, Feb 17 2017

%Y Cf. A055494.

%Y Cf. A081256, A096173.

%K nonn

%O 1,1

%A _Hugo Pfoertner_, Jun 20 2004

%E Definition corrected by _N. J. A. Sloane_, Apr 08 2010