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Primes p such that (p-1)/2, (p-2)/3, (p-3)/4, (p-4)/5 and (p-5)/6 are prime numbers.
1

%I #12 May 29 2024 18:36:05

%S 7224839,9339119,10780559,42464519,45652319,53464319,62198639,

%T 69899759,94159799,121136399,130777919,158608799,191010959,285785639,

%U 288308159,322461719,353256119,402411239,423803519

%N Primes p such that (p-1)/2, (p-2)/3, (p-3)/4, (p-4)/5 and (p-5)/6 are prime numbers.

%t Select[Prime[Range[20000000]],PrimeQ[(#-1)/2]&&PrimeQ[(#-2)/3]&&PrimeQ[(#-3)/4]&&PrimeQ[(#-4)/5]&&PrimeQ[(#-5)/6]&]

%t Select[Prime[Range[2254*10^4]],AllTrue[(#-Range[5])/Range[2,6],PrimeQ]&] (* _Harvey P. Dale_, May 29 2024 *)

%Y Cf. A093554.

%K nonn

%O 1,1

%A _Vladimir Joseph Stephan Orlovsky_, Nov 17 2010

%E Edited, terms checked and two terms added by _Klaus Brockhaus_, Nov 17 2010