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A172456
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Primes p such that (p, p+2, p+6, p+12, p+14, p+20) is a prime sextuple.
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3
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17, 1277, 1607, 3527, 4637, 71327, 97367, 113147, 191447, 290657, 312197, 416387, 418337, 421697, 450797, 566537, 795647, 886967, 922067, 1090877, 1179317, 1300127, 1464257, 1632467, 1749257, 1866857, 1901357, 2073347, 2322107
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OFFSET
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1,1
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COMMENTS
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The last digit of each of these prime numbers is 7.
The primes are always consecutive: The few ways of inserting other primes are: (p,p+2,p+4)... [impossible since one of these would be a multiple of 3]; (p,p+2,p+6),(p+8),(p+12),(p+14) [impossible since one of these would be a multiple of 5]; (p,p+2,p+6),(p+10) [impossible since one of these would be a multiple of 3]; (p,p+2,p+6),(p+12),(p+14),(p+16) [impossible since one of these would be a multiple of 3]; (p,p+2,p+6),(p+12),(p+14),(p+18) [impossible since one of these would be a multiple of 5]. - R. J. Mathar, Jun 15 2013
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REFERENCES
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R. K. Guy, Unsolved Problems in Number Theory, E30.
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LINKS
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R. L. Graham and C. B. A. Peck, Problem E1910, Amer. Math. Monthly, 75 (1968), 80-81.
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EXAMPLE
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The first two terms correspond to the sextuples (17,19,23,29,31,37) and (1277,1279,1283,1289,1291,1297).
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MAPLE
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for n from 1 by 2 to 400000 do; if isprime(n) and isprime(n+2) and isprime(n+6) and isprime(n+12) and isprime(n + 14) and isprime(n+20) then print(n) else fi; od;
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MATHEMATICA
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Select[Prime[Range[171000]], And@@PrimeQ[{#+2, #+6, #+12, #+14, #+20}]&] (* Harvey P. Dale, Jul 23 2011 *)
Select[Prime[Range[171000]], AllTrue[#+{2, 6, 12, 14, 20}, PrimeQ]&] (* or *) Select[ Partition[Prime[Range[171000]], 6, 1], Differences[#]=={2, 4, 6, 2, 6}&][[All, 1]] (* Harvey P. Dale, Sep 04 2022 *)
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CROSSREFS
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Initial members of prime quadruples (p, p+2, p+6, p+12): A172454.
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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