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A291853
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Numbers n such that (3^n - (-2)^n)/5 is prime.
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0
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3, 4, 7, 11, 83, 149, 223, 599, 647, 1373, 8423
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OFFSET
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1,1
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COMMENTS
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a(12) > 65535. Presumably, a(12) = 149497 and a(13) = 388897.
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LINKS
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EXAMPLE
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4 is in this sequence because (3^4 - (-2)^4)/5 = 13 is prime.
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MATHEMATICA
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PROG
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(Magma) [n: n in [1..1000] | IsPrimePower((3^n-(-2)^n) div 5)];
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CROSSREFS
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Cf. A107036 (numbers n such that (2^n-(-1)^n)/3 is prime).
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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