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A096174 Even numbers n such that (n^3+1)/(n+1) is prime. 8
2, 4, 6, 16, 18, 22, 28, 34, 42, 58, 60, 70, 72, 76, 78, 90, 100, 102, 106, 112, 118, 120, 132, 142, 144, 148, 154, 156, 162, 168, 174, 190, 204, 210, 216, 232, 246, 280, 288, 294, 310, 330, 352, 358, 370, 382, 384, 396, 406, 436, 448, 454, 456, 490, 496, 526 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Hugo Pfoertner, Table of n, a(n) for n = 1..10000

EXAMPLE

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.

PROG

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

CROSSREFS

Cf. A055494.

Cf. A081256 largest prime factor of n^3+1, A096173 n^3+1 is an odd semiprime.

Sequence in context: A099315 A005179 A037019 * A096173 A287681 A114874

Adjacent sequences:  A096171 A096172 A096173 * A096175 A096176 A096177

KEYWORD

nonn

AUTHOR

Hugo Pfoertner, Jun 20 2004

EXTENSIONS

Definition corrected by N. J. A. Sloane, Apr 08 2010

STATUS

approved

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Last modified January 18 18:32 EST 2018. Contains 297864 sequences.