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A046401
Numbers with exactly 3 distinct palindromic prime factors.
2
30, 42, 66, 70, 105, 110, 154, 165, 231, 385, 606, 786, 906, 1010, 1086, 1146, 1310, 1414, 1510, 1515, 1810, 1834, 1878, 1910, 1965, 2114, 2118, 2121, 2222, 2238, 2265, 2298, 2534, 2674, 2715, 2751, 2865, 2882, 3130, 3171, 3322, 3333, 3530, 3535, 3730
OFFSET
1,1
MATHEMATICA
Select[Range[4000], PrimeOmega[#]==PrimeNu[#]==3&&AllTrue[FactorInteger[#][[All, 1]], PalindromeQ]&] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Aug 27 2019 *)
CROSSREFS
Sequence in context: A087248 A249242 A189759 * A302570 A300156 A306330
KEYWORD
nonn,base
AUTHOR
Patrick De Geest, Jun 15 1998
STATUS
approved