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Primes p that are simultaneously of the forms 2*q+1, 4*r+3, 6*s+5 and 8*t+7 where q,r,s,t are primes.
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%I #25 Nov 15 2021 17:32:46

%S 23,47,1439,2879,11279,51599,209519,243119,349199,507359,700319,

%T 903359,1190639,1342079,1650959,1956719,2978399,3304079,3376559,

%U 3841679,4858559,5404319,5454719,6207599,6486479,7682399,7825439,8169599,8826479,8970959,9546959

%N Primes p that are simultaneously of the forms 2*q+1, 4*r+3, 6*s+5 and 8*t+7 where q,r,s,t are primes.

%C All terms == 23 (mod 24). All but the first == 47 (mod 48).

%H Robert Israel, <a href="/A328799/b328799.txt">Table of n, a(n) for n = 1..2000</a>

%e a(3)=1439 is a term because 1439=2*719+1=4*359+3=6*239+5=8*179+7 and 1439, 719, 359, 239 and 179 are all primes.

%p map(t -> 24*t+23, select(k -> andmap(isprime, [3*k+2,4*k+3,6*k+5,12*k+11,24*k+23]), [0, seq(k,k=1..10^6,2)]));

%Y Cf. A005385, A066179, A157358.

%K nonn

%O 1,1

%A _J. M. Bergot_ and _Robert Israel_, Nov 18 2019

%E Clarified definition. - _N. J. A. Sloane_, Nov 15 2021