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A319481
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Integers k such that uphi(k) divides k, where uphi is the unitary phi function (A047994).
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3
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1, 2, 6, 12, 168, 240, 14880, 65280, 4294901760, 7608944640, 1125874137169920, 18446744069414584320
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OFFSET
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1,2
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LINKS
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PROG
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(PARI) uphi(n) = my(f=factor(n)~); prod(i=1, #f, f[1, i]^f[2, i]-1);
isok(n) = frac(n/uphi(n)) == 0;
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CROSSREFS
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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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