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A138250 Prime numbers k such that 30*k - 1, 30*k + 1 are twin primes. 1
2, 5, 19, 41, 43, 71, 113, 131, 167, 223, 229, 281, 331, 383, 457, 461, 467, 509, 541, 593, 797, 839, 937, 947, 971, 1009, 1013, 1087, 1097, 1153, 1231, 1289, 1471, 1553, 1559, 1699, 1787, 2003, 2099, 2113, 2617, 2683, 2689, 2731, 2749, 2861, 2879, 2917 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
EXAMPLE
2*30 - 1 = 59 (prime), 2*30 + 1 = 61 (prime).
MATHEMATICA
a=30; Select[Prime[Range[250]], PrimeQ[a*#-1]&&PrimeQ[a*#+1] &]
PROG
(Magma) [n: n in [0..10000] |IsPrime(n) and IsPrime(30*n-1)and IsPrime(30*n+1)] // Vincenzo Librandi, Aug 03 2010
CROSSREFS
Sequence in context: A227632 A105889 A086085 * A140761 A077323 A215274
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified February 22 22:43 EST 2024. Contains 370265 sequences. (Running on oeis4.)