A225321 -id:A225321 - cp's OEIS frontend

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.

66747, 18248, 53097, 2037018, 142531, 1691820, 1322535, 1659002, 266251, 6185640, 95075, 2518780, 657645, 325528, 71971, 2533260, 21494113, 682318, 3114879, 6523742, 9196027, 3588090, 12492473, 816078, 14837001, 12060370, 2933065, 12212058, 3122953

Offset: 2

Robin Garcia, May 10 2013

nonn

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

Cf. A070694, A225321, A225492

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))))))

A225392 Numbers b such that b^(2^n) + 2 is prime for n from 0 to 4.

Original entry on oeis.org

22155, 1864149, 2760681, 6222765, 22687797, 25631319, 29309589, 33333069, 36490905, 56310891, 60212889, 74097849, 76008207, 80864685, 84214395, 132006225, 132621171, 137362521, 138993381, 152223885, 154185525, 175950081, 188261481, 188677335, 194279955

Offset: 1

Robin Garcia, May 06 2013

nonn

Generalized Fermat numbers of the form b^(2^n) + k with k = 2 here.

For b = 2760681, b^(2^n) + 2 is prime for n from 0 to 5

Cf. A070694, A225321

k=2;forstep(b=1,5*10^7,[4,2,2,2],i=0;for(n=0,4,m=b^2^n+k;if(isprime(m),i++;if(i>4,print([b,m,n,i])))))

a(10)-a(25) from Giovanni Resta, May 06 2013

cp's OEIS Frontend

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.

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