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A115710
Semiprimes (A001358) whose digit reversal is a square.
2
4, 9, 10, 46, 94, 121, 169, 526, 961, 982, 1042, 1273, 1405, 1843, 4069, 4633, 5221, 6313, 6511, 6937, 9235, 9481, 9886, 10201, 10609, 12538, 12769, 14023, 16171, 16327, 16582, 16723, 18085, 18463, 18811, 40219, 42817, 42931, 44353, 44521
OFFSET
1,1
EXAMPLE
46=2*23 is semiprime and 64=8^2.
MATHEMATICA
Select[Range[50000], PrimeOmega[#]==2&&IntegerQ[Sqrt[FromDigits[ Reverse[ IntegerDigits[ #]]]]]&] (* Harvey P. Dale, Mar 03 2013 *)
CROSSREFS
Sequence in context: A197125 A197129 A115688 * A082749 A220427 A115675
KEYWORD
nonn,base
AUTHOR
Giovanni Resta, Jan 31 2006
STATUS
approved