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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
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 (list; graph; refs; listen; history; text; internal format)
OFFSET
2,1
COMMENTS
Generalized Fermat numbers of the form b^(2^n) + k
LINKS
PROG
(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))))))
CROSSREFS
Sequence in context: A237925 A251057 A256002 * A234402 A235024 A235245
KEYWORD
nonn
AUTHOR
Robin Garcia, May 10 2013
STATUS
approved

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Last modified May 20 08:05 EDT 2024. Contains 372703 sequences. (Running on oeis4.)