%I #6 Oct 14 2014 19:20:19
%S 0,1,4,9,10,14,40,44,49,90,91,94,99,100,104,110,111,114,119,140,141,
%T 144,190,194,400,404,410,411,414,440,441,444,490,494,900,901,904,909,
%U 910,914,940,944,949,990,994,999,1000,1001,1004,1010,1011,1014,1040,1041
%N Nonprimes whose digits are all square.
%C Square digits are 0, 1, 4 or 9.
%H Harvey P. Dale, <a href="/A157908/b157908.txt">Table of n, a(n) for n = 1..10000</a>
%F a(n) = Theta(n^(log_4 10))
%t Select[FromDigits/@Tuples[{0,1,4,9},4],!PrimeQ[#]&] (* _Harvey P. Dale_, Oct 14 2014 *)
%Y Cf. A000290, A141468.
%K nonn,base
%O 1,3
%A _Juri-Stepan Gerasimov_, Mar 09 2009
%E Formula from _Charles R Greathouse IV_, Mar 25 2010
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