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A145315 Numbers k for which the set {30*k-13, 30*k-11, 30*k-7, 30*k-1, 30*k+1, 30*k+7, 30*k+11, 30*k+13} forms a symmetrical prime octuplet. 2
1, 43, 3772, 86022, 691263, 1940280, 2445785, 2539018, 3355288, 4492167, 4598112, 5517709, 5731956, 7466941, 8409234, 9817872, 10324700, 10390862, 12138468, 13631232, 17181592, 17382707, 17609073, 20633677, 20897582, 22760333, 23389302, 32968102, 36051016, 37215088 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
a(n) is always +/- 1 (mod 7).
LINKS
FORMULA
a(n) = (A022012(n) + 13)/30. - Hugo Pfoertner, Nov 08 2022
MATHEMATICA
spoQ[n_]:=Module[{c=30n}, And@@PrimeQ[{c-13, c-11, c-7, c-1, c+1, c+7, c+11, c+13}]]; Select[Range[23000000], spoQ] (* Harvey P. Dale, Oct 10 2011 *)
CROSSREFS
Cf. A022012.
Sequence in context: A265234 A357557 A015323 * A110704 A060485 A081795
KEYWORD
nonn
AUTHOR
Andrey V. Kulsha, Oct 07 2008
STATUS
approved

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Last modified March 1 06:29 EST 2024. Contains 370430 sequences. (Running on oeis4.)