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User talk:M. F. Hasler/drafts/A171255

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Least prime in a decade containing exactly 3 primes

41,71,131,223, 311,431,461,613, 641,853,881, 1031,1061,1091, 1301,1423,1451, 1601,1663,1693, 1783,1993,2381, 2683,2711,3163,3671, 3761,3911,4001, 4091,4153,4211, 4513,4721,4783, 4931,5231,5413, 5441,5471,5501, 5741,5861,6701, 6823,7121,7211,7451, 7481,7541,7753, 7873,8081,8231, 8291,8623,8831, 8861,9041,9341, 9461,9851,...


(PARI)

for(d=1,999,primepi(10*(d+1))-primepi(10*d) == 3|next; print1(nextprime(d*10+1)","))

Formula

a(n)=nextprime(10*A171254(n))

Crossrefs

  • ../A171251 Decades with prime triplets
  • ../A171252 Least member of decadal prime triplets
  • ../A171253 Largest member of decadal prime triplet
  • ../A171254 Decades containing exactly 3 primes
  • ../A171255 Least prime in a decade containing exactly 3 primes
  • ../A171256 Run lengths of decadal prime triplets
  • ../A171257 Least prime of a run of 3 or more consecutive decadal prime triplets

Author

M. F. Hasler 20:41, 3 January 2010 (UTC)