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A145490 Numbers k such that 6k+19 is prime and absolute value of 12k+1 is also prime. 8
-2, -1, 3, 8, 9, 13, 15, 20, 23, 29, 34, 35, 48, 55, 59, 63, 69, 73, 78, 84, 93, 100, 104, 115, 119, 134, 135, 139, 148, 150, 169, 174, 178, 185, 189, 199, 203, 210, 213, 218, 238, 254, 255, 260, 265, 268, 275, 280, 288, 289, 293, 294, 295, 308, 309, 335, 344 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

LINKS

Nathaniel Johnston, Table of n, a(n) for n = 1..10000

FORMULA

a(n)=(A145480(n-2)-1)/12 for n >= 3.

MAPLE

with(numtheory): a:=proc(n) if(isprime(6*n+19) and isprime(abs(12*n+1)))then return n: fi: return NULL: end: seq(a(n), n=-2..350); # Nathaniel Johnston, Jul 26 2011

CROSSREFS

Cf. A063908-A063913, A092109, A145471-A145490.

Sequence in context: A205391 A078045 A202624 * A057300 A076655 A101486

Adjacent sequences:  A145487 A145488 A145489 * A145491 A145492 A145493

KEYWORD

sign,easy

AUTHOR

Artur Jasinski (grafix(AT)csl.pl), Oct 11 2008

EXTENSIONS

Corrected by Arkadiusz Wesolowski, Jul 26 2011

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Last modified February 14 08:37 EST 2012. Contains 205614 sequences.