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 A046368 Numbers with exactly 2 palindromic prime factors (counted with multiplicity), and no other prime factors. 6
 4, 6, 9, 10, 14, 15, 21, 22, 25, 33, 35, 49, 55, 77, 121, 202, 262, 302, 303, 362, 382, 393, 453, 505, 543, 573, 626, 655, 706, 707, 746, 755, 766, 905, 917, 939, 955, 1057, 1059, 1111, 1119, 1149, 1267, 1337, 1441, 1454, 1514, 1565, 1574, 1594, 1661, 1765 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Intersection of A001358 and A033620; A046368 is a subsequence. - Reinhard Zumkeller, Apr 10 2011 Equivalently, semiprimes where both prime factors are palindromes. - Franklin T. Adams-Watters, Apr 11 2011 LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..1000 MATHEMATICA palQ[n_] := Reverse[x = IntegerDigits[n]] == x; Select[Range[1800], PrimeOmega[#] == 2 && And @@ palQ /@ First /@ FactorInteger[#] &] (*Jayanta Basu, Jun 23 2013 *) CROSSREFS Cf. A001358, A046400, A001358. Sequence in context: A264815 A108574 A157931 * A236108 A253106 A320969 Adjacent sequences:  A046365 A046366 A046367 * A046369 A046370 A046371 KEYWORD nonn,base,changed AUTHOR Patrick De Geest, Jun 15 1998 EXTENSIONS Definition clarified by Franklin T. Adams-Watters, Apr 11 2011 STATUS approved

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Last modified October 20 04:37 EDT 2019. Contains 328247 sequences. (Running on oeis4.)