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A366637
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Number of divisors of 7^n+1.
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9
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2, 4, 6, 8, 4, 16, 24, 16, 8, 16, 32, 16, 32, 16, 12, 64, 8, 8, 48, 16, 16, 128, 48, 8, 16, 32, 24, 32, 64, 8, 512, 32, 16, 128, 48, 1024, 256, 16, 12, 256, 64, 64, 96, 512, 32, 2048, 96, 8, 64, 2048, 640, 128, 32, 64, 384, 3072, 256, 256, 96, 64, 512, 8, 48
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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(4)=4 because 7^4+1 has divisors {1, 2, 1201, 2402}.
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MAPLE
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a:=n->numtheory[tau](7^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(7^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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