User talk:M. F. Hasler/Sequences/A238713

Came back today to this draft from 2010. Sequence A171252 is something completely different and the sequence defined below does not seem to exist as of today. — MFH 17:24, 3 March 2014 (UTC)

UPDATE: now submitted as A238713. Will move that page to there. See also A008470 and my notes /A008470.

Least member of decadal prime triplets

11,41,71,101,131,191,223,311,431,461,613,641,821,853,881,1031,1061,1091,1301,1423,1451, 1481,1601,1663,1693,1783,1871,1993,2081,2381,2683,2711,3163,3251,3461,3671,3761,3911,4001, 4091,4153,4211,4513,4721,4783,4931,5231,5413,5441,5471,5501,5651,5741,5861,6701,6823,7121, 7211,7451,7481,7541,7753,7873,8081,8231,8291,8623,8831,8861,9041,9341,9431,9461,9851,

(PARI)

for(d=1,999,primepi(10*(d+1))-primepi(10*d) >2|next; print1(nextprime(d*10+1)","))

Formula

a(n) = nextprime(10*A008470(n))

Crossrefs

• A008470: Decades with prime triplets My notes: ../A008470. Originally ../A171251
• A238713: Least member of decadal prime triplets. My notes: User talk:M. F. Hasler/Sequences/A238713
• ../A171253 Largest member of decadal prime triplet
• A008471: Exactly 3 out of 10m+1, 10m+3, 10m+7, 10m+9 areq primes. My notes: ../A008471 - originally planned to be ../A171254 : Decades containing exactly 3 primes
• ../A171255 Least prime in a decade containing exactly 3 primes
• A238716: Run lengths of decadal prime triplets. My notes: ../A238716; initially planned to be ../A171256
• A238715: Least prime of a run of 3 or more consecutive decadal prime triplets. Notes: ../A238715; initially planned to be A171257 : ../A171257

Author

— M. F. Hasler 20:36, 3 January 2010 (UTC)