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A245304
Numbers m such that m+1, m+3, m+7, m+9 and m+13 are all primes.
4
4, 10, 100, 1480, 16060, 19420, 21010, 22270, 43780, 55330, 144160, 165700, 166840, 195730, 201820, 225340, 247600, 268810, 326140, 347980, 361210, 397750, 465160, 518800, 536440, 633460, 633790, 661090, 768190, 795790, 829720, 857950, 876010, 958540
OFFSET
1,1
REFERENCES
W. SierpiƄski, 250 Problems in Elementary Number Theory. New York: American Elsevier, 1970. Problem #82, variant.
LINKS
Reinhard Zumkeller and Jens Kruse Andersen, Table of n, a(n) for n = 1..1000 (first 120 terms from Zumkeller)
FORMULA
a(n) = A022006(n)-1. - Jens Kruse Andersen, Jul 18 2014
MATHEMATICA
Select[Range[10^6], AllTrue[#+{1, 3, 7, 9, 13}, PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, May 07 2015 *)
PROG
(Haskell)
a245304 n = a245304_list !! (n-1)
a245304_list = map (pred . head) $ filter (all (== 1) . map a010051') $
iterate (zipWith (+) [1, 1, 1, 1, 1]) [1, 3, 7, 9, 13]
(PARI) forprime(p=2, 10^7, m=p-1; if(isprime(m+3)&&isprime(m+7)&&isprime(m+9)&&isprime(m+13), print1(m", "))) \\ Jens Kruse Andersen, Jul 18 2014
(Magma) [n: n in [0..10^6] | IsPrime(n+1) and IsPrime(n+3) and IsPrime(n+7) and IsPrime(n+9) and IsPrime(n+13)]; // Vincenzo Librandi, Jun 15 2015
CROSSREFS
Cf. A010051, A022006, A245305, A007811, subsequence of A125855.
Sequence in context: A261842 A153743 A370987 * A298953 A197851 A197865
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Jul 18 2014
STATUS
approved