The OEIS is supported by the many generous donors to the OEIS Foundation.

 Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 60th year, we have over 367,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”). Other ways to Give
 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A022548 Initial members of prime nonuplets (p, p+4, p+10, p+12, p+18, p+22, p+24, p+28, p+30). 34
 88789, 855709, 74266249, 964669609, 1422475909, 2117861719, 2558211559, 2873599429, 5766036949, 6568530949, 8076004609, 9853497739, 16394542249, 21171795079, 21956291869, 22741837819, 26486447149, 27254489389 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS All terms are congruent to 169 (modulo 210). - Matt C. Anderson, May 28 2015 LINKS Matt C. Anderson and Dana Jacobsen, Table of n, a(n) for n = 1..10000 [first 800 terms from Matt C. Anderson] Tony Forbes and Norman Luhn, Prime k-tuplets Norman Luhn, The first 10^6 initial members of prime 9-tuplets | pattern: d= 0, 4, 10, 12, 18, 22, 24, 28, 30, zip archive. MAPLE a := 1; for b to 25 do a := a*ithprime(b) end do; a; # so ‘a’ is the product of the primes 2 through 97 composite_small := proc (n::integer) description "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; # my technique involves isprime(m*n+o+p) # with Multiplier, Number, Offset, and Pattern p := [0, 4, 10, 12, 18, 22, 24, 28, 30]; o := [2059, 6679, 7519, 8989, 10249, 12139, 14449, 14869, 15919, 17179, 20539, 21379, 24109, 25999, 28729]; with(ArrayTools); os := Size(o, 2); ps := Size(p, 2); m := 30030; 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, Feb 13 2014 MATHEMATICA Select[Prime[Range[2 10^6]], Union[PrimeQ[# + {4, 10, 12, 18, 22, 24, 28, 30}]] == {True} &] (* Vincenzo Librandi, Sep 30 2015 *) PROG (Perl) use ntheory ":all"; say for sieve_prime_cluster(1, 1e11, 4, 10, 12, 18, 22, 24, 28, 30); # Dana Jacobsen, Sep 30 2015 (PARI) forprime(p=2, 10^30, if (isprime(p+4) && isprime(p+10) && isprime(p+12) && isprime(p+18) && isprime(p+22) && isprime(p+24) && isprime(p+28) && isprime(p+30), print1(p", "))) \\ Altug Alkan, Sep 30 2015 CROSSREFS Cf. A022545, A022546, A022547. Sequence in context: A345821 A031857 A346998 * A022013 A347853 A233038 Adjacent sequences: A022545 A022546 A022547 * A022549 A022550 A022551 KEYWORD nonn AUTHOR Warut Roonguthai STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified December 5 08:13 EST 2023. Contains 367575 sequences. (Running on oeis4.)