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A156313 Primes that cannot be written as prime(k) + prime(k+1)*m. 3

%I

%S 2,3,7,31,67,79,97,109,151,199,211,241,331,379,409,457,499,619,631,

%T 751,757,769,877,991,1039,1087,1117,1201,1231,1291,1381,1429,1471,

%U 1609,1621,1777,1861,1999,2131,2179,2269,2281,2311,2341,2389,2551,2659,2719,2797

%N Primes that cannot be written as prime(k) + prime(k+1)*m.

%C A156311(A049084(a(n))) = 0.

%H Charles R Greathouse IV, <a href="/A156313/b156313.txt">Table of n, a(n) for n = 1..10000</a>

%o (PARI) ok(t)=my(p=2); forprime(q=3,nextprime(t/2),if(t%q==p, return(0)); p=q); 1

%o select(ok, primes(100)) \\ _Charles R Greathouse IV_, Mar 13 2015

%Y Cf. A156312.

%K nonn

%O 1,1

%A _Reinhard Zumkeller_, Feb 07 2009

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Last modified September 28 05:33 EDT 2020. Contains 337392 sequences. (Running on oeis4.)