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A225560 Least numbers k for each base  b >= 2 such that N = b^(2^n) + k is prime for 7  consecutive values from  n = 0 to  n = 6 6

%I

%S 66747,18248,53097,2037018,142531,1691820,1322535,1659002,266251,

%T 6185640,95075,2518780,657645,325528,71971,2533260,21494113,682318,

%U 3114879,6523742,9196027,3588090,12492473,816078,14837001,12060370,2933065,12212058,3122953

%N Least numbers k for each base b >= 2 such that N = b^(2^n) + k is prime for 7 consecutive values from n = 0 to n = 6

%C Generalized Fermat numbers of the form b^(2^n) + k

%o (PARI) for(b=2,30,if(b%2==0,a=1,a=0);forstep(k=a,10^8,2,i=0;for(n=0,6,m=b^2^n+k;if(isprime(m),i++;if(i>6,print1(k,", ");next(3))))))

%Y Cf. A070694, A225321, A225492

%K nonn

%O 2,1

%A _Robin Garcia_, May 10 2013

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Last modified October 15 23:54 EDT 2019. Contains 328038 sequences. (Running on oeis4.)