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A245241 Integers n such that 6 * 7^n + 1 is prime. 3
0, 1, 4, 9, 99, 412, 2633, 5093, 5632, 28233, 36780, 47084, 53572 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

All terms correspond to verified primes, that is, not merely probable primes.

a(14) > 2*10^5.

LINKS

Table of n, a(n) for n=1..13.

EXAMPLE

4 is in this sequence because 6 * 7^4 + 1 = 14407, which is prime.

MATHEMATICA

Select[Range[0, 200000], PrimeQ[6 * 7^# + 1] &]

CROSSREFS

Cf. A003307, A002235, A046865, A079906, A001771, A005541, A056725, A046867, A079907.

Cf. A005537, A005538, A005539, A216889, A216890, A247260.

Sequence in context: A242097 A220972 A247009 * A115690 A115689 A061457

Adjacent sequences:  A245238 A245239 A245240 * A245242 A245243 A245244

KEYWORD

nonn,more

AUTHOR

Robert Price, Nov 14 2014

STATUS

approved

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Last modified October 19 16:17 EDT 2019. Contains 328223 sequences. (Running on oeis4.)