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A262049 Sum of the palindromic primes dividing n (with repetition). 3
0, 2, 3, 4, 5, 5, 7, 6, 6, 7, 11, 7, 0, 9, 8, 8, 0, 8, 0, 9, 10, 13, 0, 9, 10, 2, 9, 11, 0, 10, 0, 10, 14, 2, 12, 10, 0, 2, 3, 11, 0, 12, 0, 15, 11, 2, 0, 11, 14, 12, 3, 4, 0, 11, 16, 13, 3, 2, 0, 12, 0, 2, 13, 12, 5, 16, 0, 4, 3, 14, 0, 12, 0, 2, 13 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(p)=0 for primes p which are not in A002385.

The first runs of 2, 3 and 4 identical values start at a(5), a(370) and a(2776191), respectively. - Giovanni Resta, Sep 09 2015

LINKS

Table of n, a(n) for n=1..75.

FORMULA

Let n=product_i p(i)^e(i), then a(n)=sum_{i,p(i) in A002113} e(i)*p(i).

a(n) <= A001414(n).

MAPLE

A262049 := proc(n)

    local a, d ;

    a := 0 ;

    for d in ifactors(n)[2] do

        if isA002113(op(1, d)) then

            a := a+op(1, d)*op(2, d) ;

        end if;

    end do:

    a ;

end proc:

seq(A262049(n), n=1..120) ;

MATHEMATICA

palQ[n_] := Block[{d = IntegerDigits@ n}, d == Reverse@ d]; {0}~Join~

Table[Total@ Select[Flatten[Table[#1, {#2}] & @@@ FactorInteger@ n], palQ], {n, 2, 75}] (* Michael De Vlieger, Sep 09 2015 *)

CROSSREFS

Cf. A002113, A002385.

Sequence in context: A118503 A086295 A159303 * A001414 A134875 A134889

Adjacent sequences:  A262046 A262047 A262048 * A262050 A262051 A262052

KEYWORD

nonn,base

AUTHOR

R. J. Mathar, Sep 09 2015

STATUS

approved

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Last modified November 15 18:59 EST 2019. Contains 329149 sequences. (Running on oeis4.)