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A046355 Composite numbers with only palindromic prime factors whose sum is palindromic (counted with multiplicity). 4
4, 6, 8, 9, 10, 12, 14, 15, 16, 18, 20, 24, 27, 28, 40, 45, 48, 54, 121, 308, 440, 495, 528, 594, 735, 784, 875, 882, 1050, 1120, 1250, 1260, 1331, 1344, 1500, 1512, 1600, 1701, 1800, 1920, 2025, 2048, 2101, 2121, 2160, 2304, 2430, 2525, 2592, 2751, 2916, 3030 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Subsequence of the numbers k in A046349 such that A262049(k) is in A002113. - R. J. Mathar, Sep 09 2015

LINKS

Giovanni Resta, Table of n, a(n) for n = 1..10000

EXAMPLE

3030 = 2 * 3 * 5 * 101 -> 2 + 3 + 5 + 101 = 111 and 111 is a palindrome.

MAPLE

isA046355 := proc(n)

    local sofpp ;

    if isA046349(n) then

        sofpp := A262049(n) ;

        isA002113(sofpp) ;

    else

        false;

    end if;

end proc:

for n from 2 to 400 do

    if isA046355(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, 3100], !PrimeQ[#] && And@@palQ/@Join[{Total[Times@@@(x=FactorInteger[#])]}, First/@x]&] (* Jayanta Basu, Jun 05 2013 *)

CROSSREFS

Cf. A046356, A046357.

Sequence in context: A070807 A246282 A046352 * A163122 A202259 A050655

Adjacent sequences:  A046352 A046353 A046354 * A046356 A046357 A046358

KEYWORD

nonn,base

AUTHOR

Patrick De Geest, Jun 15 1998.

STATUS

approved

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Last modified July 17 01:41 EDT 2018. Contains 312693 sequences. (Running on oeis4.)