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A180506 The largest palindromic prime dividing n, or 0 if such a prime does not exist. 2
2, 3, 2, 5, 3, 7, 2, 3, 5, 11, 3, 0, 7, 5, 2, 0, 3, 0, 5, 7, 11, 0, 3, 5, 2, 3, 7, 0, 5, 0, 2, 11, 2, 7, 3, 0, 2, 3, 5, 0, 7, 0, 11, 5, 2, 0, 3, 7, 5, 3, 2, 0, 3, 11, 7, 3, 2, 0, 5, 0, 2, 7, 2, 5, 11, 0, 2, 3, 7, 0, 3, 0, 2, 5, 2, 11, 3, 0, 5, 3, 2, 0, 7, 5, 2, 3, 11, 0, 5, 7, 2, 3, 2, 5, 3, 0, 7, 11, 5, 101, 3, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

LINKS

Table of n, a(n) for n=2..103.

MAPLE

read("transforms") : isA002113 := proc(n) simplify(digrev(n) = n ); end proc:

isA002385 := proc(n) isprime(n) and isA002113(n) ; end proc:

A180506 := proc(n) fs := sort(convert(numtheory[factorset](n), list)) ; for i from 1 to nops(fs) do if isA002385(op(-i, fs)) then return op(-i, fs) ; end if; end do: return 0 ; end proc:

seq(A180506(n), n=2..104) ; # R. J. Mathar, Sep 19 2010

CROSSREFS

Cf. A002385.

Sequence in context: A090662 A088387 A197861 * A273283 A276440 A162325

Adjacent sequences:  A180503 A180504 A180505 * A180507 A180508 A180509

KEYWORD

base,nonn

AUTHOR

Giovanni Teofilatto, Sep 09 2010

EXTENSIONS

Offset and some values corrected by R. J. Mathar, Sep 19 2010

STATUS

approved

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Last modified February 21 15:58 EST 2018. Contains 299414 sequences. (Running on oeis4.)