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A268067 Numbers n such that 1 + 2^n + 3^n + 5^n is prime. 5
1, 17, 1295 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Next term, if it exists, is greater than 30000.

LINKS

Table of n, a(n) for n=1..3.

MATHEMATICA

Select[Range[0, 2000], PrimeQ[1 + 2^# + 3^# + 5^#] &]

PROG

(PARI) lista(nn) = for(n=0, nn, if(ispseudoprime(1 + 2^n + 3^n + 5^n), print1(n, ", "))); \\ Altug Alkan, Jan 25 2016

CROSSREFS

Cf. A076515, A268064, A268065.

Sequence in context: A172456 A022012 A022546 * A188717 A266866 A289945

Adjacent sequences:  A268064 A268065 A268066 * A268068 A268069 A268070

KEYWORD

nonn,bref,more

AUTHOR

Vaclav Kotesovec, Jan 25 2016

STATUS

approved

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Last modified February 21 05:23 EST 2020. Contains 332086 sequences. (Running on oeis4.)