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A366665
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Number of divisors of 9^n+1.
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9
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2, 4, 4, 8, 8, 12, 8, 16, 4, 16, 8, 16, 64, 16, 16, 48, 4, 16, 16, 16, 32, 128, 32, 16, 16, 128, 16, 32, 64, 16, 128, 32, 4, 64, 32, 384, 256, 32, 64, 128, 32, 32, 1024, 128, 64, 384, 16, 16, 64, 512, 64, 256, 128, 64, 512, 192, 512, 512, 32, 8, 2048, 64, 16
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OFFSET
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0,1
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LINKS
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FORMULA
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EXAMPLE
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a(2)=4 because 9^2+1 has divisors {1, 2, 41, 82}.
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MAPLE
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a:=n->numtheory[tau](9^n+1):
seq(a(n), n=0..100);
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MATHEMATICA
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PROG
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(PARI) a(n) = numdiv(9^n+1);
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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