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 A063753 Cototient(n) is a square and sets a new record for squares. 2
 2, 6, 21, 24, 54, 96, 189, 216, 345, 384, 420, 796, 864, 1332, 1536, 1680, 2340, 3300, 3780, 5328, 6144, 6516, 6720, 8260, 8484, 9360, 10500, 13200, 14532, 15120, 18340, 19476, 20580, 24576, 26064, 26628, 26880, 29700, 33396, 33936, 34020 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Harry J. Smith, Table of n, a(n) for n=1,...,275 PROG (PARI)a=0; for(n=1, 7000, x=n-eulerphi(n); if(issquare(x), b=x; if(b>a, a=b; print(n)))) (PARI) { n=0; a=0; for (m=1, 10^9, if (issquare(b=m - eulerphi(m)), if (b>a, a=b; write("b063753.txt", n++, " ", m); if (n==275, break))) ) } [From Harry J. Smith, Aug 29 2009] CROSSREFS Cf. A051953. Sequence in context: A103160 A242819 A126099 * A066893 A004192 A104143 Adjacent sequences:  A063750 A063751 A063752 * A063754 A063755 A063756 KEYWORD easy,nonn AUTHOR Jason Earls (zevi_35711(AT)yahoo.com), Aug 11 2001 EXTENSIONS More terms from Dean Hickerson, Aug 22 2001 STATUS approved

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