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A063755 Squares n which are divisible by phi(n). 1
1, 4, 16, 36, 64, 144, 256, 324, 576, 1024, 1296, 2304, 2916, 4096, 5184, 9216, 11664, 16384, 20736, 26244, 36864, 46656, 65536, 82944, 104976, 147456, 186624, 236196, 262144, 331776, 419904, 589824, 746496, 944784, 1048576, 1327104 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Harry J. Smith, Table of n, a(n) for n=1,...,160

MATHEMATICA

Select[ Range[ 1, 2000 ], Mod[ #^2, EulerPhi[ #^2 ] ]==0& ]^2

Select[Range[2000]^2, Divisible[#, EulerPhi[#]]&] (* Harvey P. Dale, Dec 11 2010 *)

PROG

(PARI) j=[]; for(n=1, 2000, if(Mod(n^2, eulerphi(n^2))==0, j=concat(j, n^2))); j

(PARI) { n=0; for (m=1, 10^9, s=m^2; if (s%eulerphi(s)==0, write("b063755.txt", n++, " ", s); if (n==160, break)) ) } \\ Harry J. Smith, Aug 29 2009

CROSSREFS

Cf. A000010, A049237, A007694. Squares arising in A007694.

Sequence in context: A221285 A121317 A238259 * A166721 A085040 A030179

Adjacent sequences:  A063752 A063753 A063754 * A063756 A063757 A063758

KEYWORD

nonn

AUTHOR

Jason Earls, Aug 14 2001

EXTENSIONS

More terms from Dean Hickerson, Aug 15 2001

STATUS

approved

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Last modified February 24 12:13 EST 2020. Contains 332209 sequences. (Running on oeis4.)