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 A027570 Initial members of prime decaplets (p, p+2, p+6, p+12, p+14, p+20, p+24, p+26, p+30, p+32). 33
 9853497737, 21956291867, 22741837817, 164444511587, 179590045487, 217999764107, 231255798857, 242360943257, 666413245007, 696391309697, 867132039857, 974275568237, 976136848847, 1002263588297, 1086344116367 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS All terms are congruent to 167 (modulo 210). - Matt C. Anderson, May 29 2015 LINKS Matt C. Anderson and Dana Jacobsen, Table of n, a(n) for n = 1..10000 [first 100 terms by Matt C. Anderson] T. Forbes, Prime k-tuplets MAPLE a := 1: for b to 25 do a := a*ithprime(b): end do: a; # now 'a' is the product of the primes less than 100. composite_small := proc (n::integer) description "procedure to determine if n has a prime factor less than 100"; if igcd(2305567963945518424753102147331756070, n) = 1 then return false else return true; end if; end proc: # so composite_small tests if there are any factors 2 through 97. #begin initialization section p := [0, 2, 6, 12, 14, 20, 24, 26, 30, 32]; o := [7517, 10247, 12137, 14447, 14867, 17177, 21377, 24107, 25997, 28727]; m := 30030; #end initialization section # implement isprime(m*n+o+p) with(ArrayTools): os:=Size(o, 2): ps:=Size(p, 2): #here ps is 10 so a prime constellation of length 10. loopstop := 10^11: loopstart := 0: for n from loopstart to loopstop do for a to os do counter := 0; wc := 0; wd := 0;   while `and`(wd > -10, wd < ps) do   wd := wd+1;   if composite_small(m*n+o[a]+p[wd]) = false then wd := wd+1   else wd := -10 end if;   end do; if wd >= 9 then while `and`(counter >= 0, wc < ps) do   wc := wc+1;   if isprime(m*n+o[a]+p[wc]) then counter := counter+1;   else counter := -1   end if; end do; end if; if counter = ps then print(m*n+o[a]) end if; end do: end do: # Matt C. Anderson, Apr 15 2015 PROG (Perl) use ntheory ":all"; say for sieve_prime_cluster(1, 1e13, 2, 6, 12, 14, 20, 24, 26, 30, 32); # Dana Jacobsen, Sep 30 2015 CROSSREFS Sequence in context: A256622 A022251 A015385 * A202362 A204058 A154532 Adjacent sequences:  A027567 A027568 A027569 * A027571 A027572 A027573 KEYWORD nonn AUTHOR STATUS approved

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