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A324041 Nonpalindromic integers with palindromic product of divisors. 0
26, 49, 2285, 1109111, 3069307, 12028229, 12866669, 110091011, 10207355549, 11010911011, 11100910111, 13579355059, 30101273647, 30693069307, 111283619361 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Many terms of A327325 are palindromes, hence this sequence.

Intersection of A029742 and A327325.

a(16) > 3.5*10^11. - Giovanni Resta, Sep 04 2019

LINKS

Table of n, a(n) for n=1..15.

EXAMPLE

Divisors of 26 are : 1,2,13,26 and 1*2*13*26=676.

MATHEMATICA

Select[Range[3200000], !PalindromeQ[#] && PalindromeQ[#^(DivisorSigma[0, #]/2)] &] (* Amiram Eldar, Sep 02 2019 *)

PROG

(PARI) ispal(n) = my(d=digits(n)); d == Vecrev(d);

isok(n) = !ispal(n) && ispal(vecprod(divisors(n)));

CROSSREFS

Cf. A002113, A007955, A029742, A327325.

Sequence in context: A118367 A316120 A261932 * A137263 A073249 A044078

Adjacent sequences: A324038 A324039 A324040 * A324042 A324043 A324044

KEYWORD

nonn,base,more

AUTHOR

Michel Marcus, Sep 02 2019

EXTENSIONS

a(8)-a(15) from Giovanni Resta, Sep 04 2019

STATUS

approved

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Last modified November 29 07:12 EST 2022. Contains 358422 sequences. (Running on oeis4.)