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 A157908 Nonprimes whose digits are all square. 2
 0, 1, 4, 9, 10, 14, 40, 44, 49, 90, 91, 94, 99, 100, 104, 110, 111, 114, 119, 140, 141, 144, 190, 194, 400, 404, 410, 411, 414, 440, 441, 444, 490, 494, 900, 901, 904, 909, 910, 914, 940, 944, 949, 990, 994, 999, 1000, 1001, 1004, 1010, 1011, 1014, 1040, 1041 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 COMMENTS Square digits are 0, 1, 4 or 9. LINKS Harvey P. Dale, Table of n, a(n) for n = 1..10000 FORMULA a(n) = Theta(n^(log_4 10)) MATHEMATICA Select[FromDigits/@Tuples[{0, 1, 4, 9}, 4], !PrimeQ[#]&] (* Harvey P. Dale, Oct 14 2014 *) CROSSREFS Cf. A000290, A141468. Sequence in context: A243170 A054294 A198097 * A064973 A133764 A163643 Adjacent sequences:  A157905 A157906 A157907 * A157909 A157910 A157911 KEYWORD nonn,base AUTHOR Juri-Stepan Gerasimov, Mar 09 2009 EXTENSIONS Formula from Charles R Greathouse IV, Mar 25 2010 STATUS approved

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Last modified April 22 11:46 EDT 2019. Contains 322330 sequences. (Running on oeis4.)