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A046392 Palindromes with exactly 2 distinct prime factors. 2

%I

%S 6,22,33,55,77,111,141,161,202,262,303,323,393,454,505,515,535,545,

%T 565,626,707,717,737,767,818,838,878,898,939,949,959,979,989,1111,

%U 1441,1661,1991,3113,3223,3443,3883,7117,7447,7997,9119,9229,9449,10001

%N Palindromes with exactly 2 distinct prime factors.

%t pdpfQ[n_]:=Module[{idn=IntegerDigits[n]},idn==Reverse[idn] && PrimeNu[n] == PrimeOmega[n] == 2]; Select[Range[11000],pdpfQ] (* _Harvey P. Dale_, Dec 16 2012 *)

%Y Cf. A046328, A046408.

%K nonn,base

%O 1,1

%A _Patrick De Geest_, Jun 15 1998.

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Last modified March 20 23:22 EDT 2019. Contains 321354 sequences. (Running on oeis4.)