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A108134 Values of n such that n-1 and n+1 are twin primes and 3*n^9-1 and 3*n^9+1 are also twin primes. 0
4, 270, 37200, 57900, 63690, 80910, 150960, 256470, 367230, 405990, 577980, 641580, 706920, 1479480, 1547880, 1730580, 2026470, 2081160, 2210280, 2374530, 2423040, 2583240, 3090780, 3437220, 3510810, 4140420, 4441530, 4847460 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

EXAMPLE

270 is in the sequence because 270-1=269 and 270+1=271 are twin primes and 3*270^9-1=22876792454960999999999 and 3*270^9+1=22876792454961000000001 are also twin primes.

MATHEMATICA

fQ[n_] := Block[{p = n + 1}, PrimeQ[p + 1] && PrimeQ[3p^9 - 1] && PrimeQ[3p^9 + 1]]; Select[ Prime[ Range[408581]], fQ[ # ] &] + 1 (from Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 09 2005)

CROSSREFS

Sequence in context: A052136 A089667 A119008 * A000320 A101758 A134786

Adjacent sequences:  A108131 A108132 A108133 * A108135 A108136 A108137

KEYWORD

nonn

AUTHOR

Ray G. Opao (1260(AT)email.com), Jun 05 2005

EXTENSIONS

More terms from Robert G. Wilson v (rgwv(AT)rgwv.com), Jun 09 2005

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Last modified February 17 06:27 EST 2012. Contains 205998 sequences.