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A166156
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Numbers k such that phi(k) = number of perfect partitions of (k-1).
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0
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1, 2, 4, 8, 16, 20, 32, 64, 112, 128, 256, 512, 1024, 2048, 2816, 4096, 8192, 13312, 16384, 32768, 65536, 131072, 262144, 278528, 524288, 1000512, 1048576, 1245184, 2097152, 4194304, 8388608, 16777216, 24117248, 33554432, 67108864
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OFFSET
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1,2
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COMMENTS
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LINKS
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MATHEMATICA
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f[1] = 1; f[n_] := f[n] = Plus @@ (f /@ Most @ Divisors[n]); Select[Range[1000], f[#] == EulerPhi[#] &] (* Amiram Eldar, Feb 29 2020 *)
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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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EXTENSIONS
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Index in the definition corrected, and extended by R. J. Mathar, Oct 10 2009
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STATUS
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approved
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