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A171247 Numbers n such that 1+20^n+200^n is prime. 0
0, 19, 59, 291, 327, 3951 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

No more terms up to n=6900.

LINKS

Table of n, a(n) for n=0..5.

PROG

(PARI) is(n)=ispseudoprime(1+20^n+200^n) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Sequence in context: A236462 A139981 A235705 * A270818 A206426 A211145

Adjacent sequences:  A171244 A171245 A171246 * A171248 A171249 A171250

KEYWORD

nonn

AUTHOR

Jason Earls, Dec 06 2009

STATUS

approved

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Last modified October 21 21:25 EDT 2021. Contains 348155 sequences. (Running on oeis4.)