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A292714
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Composite numbers k such that phi(x) = psi(k)*phi(k) has no solution.
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0
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2197, 4934, 5386, 7606, 10774, 11434, 15212, 15214, 15634, 16294, 17146, 18134, 18374, 18994, 19466, 20134, 20362, 23194, 23451, 24051, 24874, 25526, 25934, 26326, 27411, 27561, 27994, 28486, 28561, 30034, 31334, 31366, 36748, 37834, 38074, 40694, 44054, 46234, 47494, 49834
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OFFSET
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1,1
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COMMENTS
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Or composite numbers k such that A007434(k) is not a totient number (A002202).
Prime power terms are 13^3, 13^4, 353^2, 457^2, 733^2, 877^2, 997^2, ...
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LINKS
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EXAMPLE
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4934 = 2*2467 is a term because psi(4934)*phi(4934) = (2^2 - 1)*(2467^2 - 1) = 2^3*3^3*137*617 is not a totient number (A002202).
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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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