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A070305 Numbers n such that Card(k>0 : phi(k)=phi(n)) = tau(n). 0
2, 4, 8, 10, 11, 14, 16, 23, 27, 28, 29, 31, 32, 38, 47, 53, 59, 64, 67, 71, 79, 83, 86, 100, 103, 107, 114, 125, 127, 128, 131, 136, 137, 139, 147, 149, 151, 167, 170, 172, 173, 176, 179, 191, 197, 199, 202, 211, 223, 227, 229, 235, 239, 251, 256, 263, 265, 269 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

FORMULA

A070241(n)=A00005(n)

PROG

(PARI) for(n=1, 350, if(sum(i=1, 3*n, if(eulerphi(n)-eulerphi(i), 0, 1))==numdiv(n), print1(n, ", ")))

CROSSREFS

Sequence in context: A028836 A028838 A178332 * A174567 A178330 A029992

Adjacent sequences:  A070302 A070303 A070304 * A070306 A070307 A070308

KEYWORD

easy,nonn

AUTHOR

Benoit Cloitre (benoit7848c(AT)orange.fr), May 10 2002

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Last modified February 17 02:08 EST 2012. Contains 205978 sequences.