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A046351 Palindromic composite numbers with only palindromic prime factors. 4
4, 6, 8, 9, 22, 33, 44, 55, 66, 77, 88, 99, 121, 202, 242, 252, 262, 303, 343, 363, 393, 404, 484, 505, 525, 606, 616, 626, 686, 707, 808, 909, 939, 1111, 1331, 1441, 1661, 1991, 2112, 2222, 2662, 2772, 2882, 3333, 3443, 3773, 3883, 3993, 4224, 4444, 5445 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..51.

FORMULA

(A032350 INTERSECT A033620) MINUS {1}. - R. J. Mathar, Sep 09 2015

MATHEMATICA

palQ[n_]:=Reverse[x=IntegerDigits[n]]==x; Select[Range[4, 5500], !PrimeQ[#]&&And@@palQ/@Join[{#}, First/@FactorInteger[#]]&](* Jayanta Basu, Jun 05 2013 *)

CROSSREFS

Cf. A033620, A046349, A046350.

Sequence in context: A032350 A078337 * A161732 A066307 A287198 A099071

Adjacent sequences:  A046348 A046349 A046350 * A046352 A046353 A046354

KEYWORD

nonn,base

AUTHOR

Patrick De Geest, Jun 15 1998.

STATUS

approved

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Last modified November 16 04:54 EST 2018. Contains 317257 sequences. (Running on oeis4.)