A121762 Single (or isolated or non-twin) primes of form 6n-1.
23, 47, 53, 83, 89, 113, 131, 167, 173, 233, 251, 257, 263, 293, 317, 353, 359, 383, 389, 401, 443, 449, 467, 479, 491, 503, 509, 557, 563, 587, 593, 647, 653, 677, 683, 701, 719, 743, 761, 773, 797, 839, 863, 887, 911, 929, 941, 947, 953, 971, 977, 983, 1013
Offset: 1
Keywords
Links
- Zak Seidov, Table of n, a(n) for n = 1..10000
Programs
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Magma
[n: n in [1..1050] | (n mod 6 eq 5) and not IsPrime(n+2) and IsPrime(n)]; // G. C. Greubel, Feb 26 2019
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Mathematica
Select[Table[6n - 1, {n, 200}], PrimeQ[ # ] && ! PrimeQ[ # + 2] &] (* Ray Chandler, Aug 22 2006 *) -
PARI
is(n)=n%6==5 && isprime(n) && !isprime(n+2) \\ Charles R Greathouse IV, Apr 04 2016
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Sage
[n for n in (1..1050) if mod(n,6)==5 and not is_prime(n+2) and is_prime(n)] # G. C. Greubel, Feb 26 2019
Extensions
Extended by Ray Chandler, Aug 22 2006
Comments