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A046853
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Denominator of sum of reciprocals of first n palindromic primes.
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2
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2, 6, 30, 210, 2310, 233310, 30563610, 4615105110, 835334024910, 159548798757810, 49938774011194530, 17628387225951669090, 6575388435279972570570, 2518373770712229494528310
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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LINKS
| Vincenzo Librandi, Table of n, a(n) for n = 1..100
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EXAMPLE
| 1/2 + 1/3 + 1/5 + 1/7 + 1/11 + 1/101 + ... gives 1/2, 5/6, 31/30, 247/210, ...
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MAPLE
| palQ[n_]:=Module[{idn=IntegerDigits[n]}, idn==Reverse[idn]]; Denominator[Accumulate[1/#&/@Select[Prime[Range[100]], palQ]] (* Vincenzo Librandi, Dec 30 2011 *)
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CROSSREFS
| Cf. A046852, A002385.
Sequence in context: A118491 A088257 A058694 * A136351 A071290 A185693
Adjacent sequences: A046850 A046851 A046852 * A046854 A046855 A046856
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KEYWORD
| nonn,base,easy
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AUTHOR
| G. L. Honaker, Jr. (honak3r(AT)gmail.com)
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EXTENSIONS
| More terms from Erich Friedman (efriedma(AT)stetson.edu), Jun 03 2001
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