A274507 Primes one more than the sum over a pair of prime numbers that differ by 8.
19, 31, 67, 127, 151, 211, 271, 307, 547, 727, 787, 811, 907, 967, 991, 1447, 1531, 1831, 1867, 2131, 2467, 2647, 2887, 2971, 3967, 5107, 5227, 5407, 5431, 5827, 6091, 6427, 6451, 6607, 6907, 6991, 7411, 8191, 8431, 8707, 9511, 10111
Offset: 1
Keywords
Examples
19 = 5 + 13 + 1. Note that, (19-9)/2 = 5 and (19+7)/2 = 13 and the prime pairs 5 and 13 differ by 8. 31 = 11 + 19 + 1. Note that, (31-9)/2 = 11 and (31+7)/2 = 19 and the prime pairs 11 and 19 differ by 8.
Programs
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Mathematica
Select[2 # + 9 &@ Select[Prime@ Range[10^3], PrimeQ[# + 8] &], PrimeQ] (* Michael De Vlieger, Jun 26 2016 *)
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PARI
lista(nn)=forprime(p=3, nn, if (isprime(p+8) && isprime(q=2*p+9), print1(q, ", "))); \\ Michel Marcus, Jun 25 2016
Comments