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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
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
Sequence in context: A316120 A261932 A364025 * A137263 A073249 A044078
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 May 16 15:40 EDT 2024. Contains 372554 sequences. (Running on oeis4.)