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 A046394 Palindromes with exactly 4 distinct prime factors. 1
 858, 2002, 2442, 3003, 4774, 5005, 5115, 6666, 10101, 15351, 17871, 22422, 22722, 24242, 26562, 26962, 28482, 35853, 36363, 41314, 43734, 43834, 45654, 47874, 49494, 49794, 49894, 51015, 51315, 51415, 53535, 53835, 53935, 56865, 58485 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Robert Israel, Table of n, a(n) for n = 1..10000 MAPLE filter:= proc(n) local F;   F:= ifactors(n)[2];   nops(F)=4 and max(map(t->t[2], F))=1 end proc: makepali:= proc(n, d) local L;   L:= convert(n, base, 10);   if d::even then 10^(d/2)*n + add(L[i]*10^(d/2-i), i=1..d/2)   else 10^((d-1)/2)*n + add(L[i]*10^((d+1)/2-i), i=2..(d+1)/2)   fi end proc: select(filter, [seq(seq(makepali(x, d),    x=10^ceil(d/2-1)..10^ceil(d/2)-1), d=1..6)]); # Robert Israel, Jun 05 2018 CROSSREFS Cf. A046330, A046410. Sequence in context: A251453 A087002 A256743 * A163304 A252237 A284074 Adjacent sequences:  A046391 A046392 A046393 * A046395 A046396 A046397 KEYWORD nonn,base AUTHOR Patrick De Geest, Jun 15 1998 STATUS approved

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Last modified March 23 18:13 EDT 2019. Contains 321433 sequences. (Running on oeis4.)