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A046392 Palindromes with exactly 2 distinct prime factors. 2
6, 22, 33, 55, 77, 111, 141, 161, 202, 262, 303, 323, 393, 454, 505, 515, 535, 545, 565, 626, 707, 717, 737, 767, 818, 838, 878, 898, 939, 949, 959, 979, 989, 1111, 1441, 1661, 1991, 3113, 3223, 3443, 3883, 7117, 7447, 7997, 9119, 9229, 9449, 10001 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..48.

MATHEMATICA

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

CROSSREFS

Cf. A046328, A046408.

Sequence in context: A020195 A035134 A075799 * A046408 A123017 A264043

Adjacent sequences:  A046389 A046390 A046391 * A046393 A046394 A046395

KEYWORD

nonn,base

AUTHOR

Patrick De Geest, Jun 15 1998.

STATUS

approved

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Last modified February 20 08:43 EST 2019. Contains 320325 sequences. (Running on oeis4.)