A125502 (Product of successive primes minus 2) divided by 7 is prime.
4127, 49727, 212627, 565727, 697727, 1152227, 3102227, 3486227, 5742227, 7488227, 8078627, 8848127, 10837727, 14200127, 23041427, 41870627, 50437727, 59044127, 68766227, 70088927, 91008227, 115141727, 118573727, 122641427
Offset: 1
Examples
167*173 = 28891, (28891-2)/7 = 4127 the first entry.
Links
- Harvey P. Dale, Table of n, a(n) for n = 1..1000
Crossrefs
Cf. A123921.
Programs
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Mathematica
Select[(Times@@@Partition[Prime[Range[5000]],2,1]-2)/7,PrimeQ] (* Harvey P. Dale, Sep 03 2015 *)
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PARI
g(n,p) = { for(x=1,n, y=prime(x)*prime(x+1)-2; if(y%p==0,if(isprime(y/p), print1(y/p",")))) }
Extensions
Typo in example corrected by Harvey P. Dale, Sep 03 2015