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 A227323 Prime(k) such that each of the three preceding and also each of the three following primes are twin primes. 0
 11, 1039, 2099, 4253, 9433, 9437, 62983, 62987, 72229, 72251, 91121, 386401, 392269, 392279, 495589, 495611, 626617, 663583, 663587, 754973, 873553, 908857, 909301, 909317, 909319, 909329, 972137, 1006309, 1006331, 1138393, 1138409, 1159201 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS The union of sequences A069456 and A227063. Prime(k) such that prime(k-i), i=1..3, and prime(k+i), i=1..3 are in A001097. LINKS MAPLE istwp := proc(n)     if isprime(n) then         if isprime(n+2) or isprime(n-2) then             true;         else             false;         end if;     else         false;     end if; end proc: for i from 4 do     p := ithprime(i) ;     p1 := prevprime(p) ;     if istwp(p1) then         p2 := prevprime(p1) ;         if istwp(p2) then             p3 := prevprime(p2) ;             if istwp(p3) then                 p1 := nextprime(p) ;                 if istwp(p1) then                     p2 := nextprime(p1) ;                     if istwp(p2) then                         p3 := nextprime(p2) ;                         if istwp(p3) then                             printf("%d\n", p) ;                         end if;                     end if;                 end if;             end if;         end if;     end if; end do: # R. J. Mathar, Jul 13 2013 CROSSREFS Sequence in context: A046187 A234634 A004811 * A126197 A090814 A347846 Adjacent sequences:  A227320 A227321 A227322 * A227324 A227325 A227326 KEYWORD nonn AUTHOR Irina Gerasimova, Jul 06 2013 EXTENSIONS Corrected by R. J. Mathar, Jul 13 2013 STATUS approved

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Last modified December 4 04:49 EST 2021. Contains 349469 sequences. (Running on oeis4.)