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A115893 Numbers n such that sigma(n) times the n-th prime is a palindrome. 1
1, 2, 5, 4813, 47619 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

No additional terms up to 5,000,000. - Harvey P. Dale, Sep 14 2012

LINKS

Table of n, a(n) for n=1..5.

EXAMPLE

sigma(47619)*p(47619)=82992*580477=48174947184.

MATHEMATICA

dspQ[n_]:=Module[{c=IntegerDigits[DivisorSigma[1, n]Prime[n]]}, c == Reverse[c]]; Select[Range[50000], dspQ] (* Harvey P. Dale, Sep 14 2012 *)

CROSSREFS

Cf. A084122, A115890, A115894.

Sequence in context: A306747 A187604 A082815 * A323338 A057678 A090071

Adjacent sequences:  A115890 A115891 A115892 * A115894 A115895 A115896

KEYWORD

nonn,base

AUTHOR

Giovanni Resta, Feb 06 2006

STATUS

approved

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Last modified October 16 12:52 EDT 2019. Contains 328060 sequences. (Running on oeis4.)