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A124198 Numbers n such that 21*n + 1 is prime. 0
2, 6, 10, 16, 18, 20, 22, 26, 30, 32, 36, 42, 46, 48, 50, 52, 62, 68, 70, 76, 82, 92, 96, 102, 108, 110, 116, 120, 126, 128, 130, 136, 146, 148, 158, 160, 168, 170, 172, 176, 178, 182, 186, 198, 200, 202, 206, 220, 222, 228, 230, 236, 238, 246, 248, 258, 262, 278 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

EXAMPLE

If n=148 then (21*n +1) = 3109 (prime).

PROG

(MAGMA) [n: n in [0..300] | IsPrime(21*n + 1)] [From Vincenzo Librandi (vincenzo.librandi(AT)tin.it)

CROSSREFS

Cf. A024905, A124127.

Sequence in context: A184426 A097022 A137236 * A032426 A195957 A183575

Adjacent sequences:  A124195 A124196 A124197 * A124199 A124200 A124201

KEYWORD

nonn

AUTHOR

Parthasarathy Nambi (PachaNambi(AT)yahoo.com), Dec 06 2006

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Last modified February 15 13:20 EST 2012. Contains 205798 sequences.