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A046349 Composite numbers with only palindromic prime factors. 4
4, 6, 8, 9, 10, 12, 14, 15, 16, 18, 20, 21, 22, 24, 25, 27, 28, 30, 32, 33, 35, 36, 40, 42, 44, 45, 48, 49, 50, 54, 55, 56, 60, 63, 64, 66, 70, 72, 75, 77, 80, 81, 84, 88, 90, 96, 98, 99, 100, 105, 108, 110, 112, 120, 121, 125, 126, 128, 132, 135, 140, 144, 147, 150 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..3020

FORMULA

A033620 INTERSECT A002808. - R. J. Mathar, Sep 09 2015

MAPLE

isA046349 := proc(n)

    simplify(isA033620(n) and not isprime(n)) ;

end proc:

for n from 2 to 300 do

    if isA046349(n) then

        printf("%d, ", n) ;

    end if;

end do: # R. J. Mathar, Sep 09 2015

MATHEMATICA

palQ[n_]:=Reverse[x=IntegerDigits[n]]==x; Select[Range[4, 150], !PrimeQ[#]&&And@@palQ/@First/@FactorInteger[#]&] (* Jayanta Basu, Jun 05 2013 *)

CROSSREFS

Cf. A033620, A046350, A046351.

Sequence in context: A077091 A174891 A051035 * A115683 A175526 A192506

Adjacent sequences:  A046346 A046347 A046348 * A046350 A046351 A046352

KEYWORD

nonn,base,easy

AUTHOR

Patrick De Geest, Jun 15 1998

STATUS

approved

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Last modified July 20 11:55 EDT 2018. Contains 312804 sequences. (Running on oeis4.)