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A046853 Denominator of sum of reciprocals of first n palindromic primes. 2
2, 6, 30, 210, 2310, 233310, 30563610, 4615105110, 835334024910, 159548798757810, 49938774011194530, 17628387225951669090, 6575388435279972570570, 2518373770712229494528310 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..100

EXAMPLE

1/2 + 1/3 + 1/5 + 1/7 + 1/11 + 1/101 + ... gives 1/2, 5/6, 31/30, 247/210, ...

MATHEMATICA

palQ[n_]:=Module[{idn=IntegerDigits[n]}, idn==Reverse[idn]]; Denominator[Accumulate[1/#&/@Select[Prime[Range[100]], palQ]] (* Vincenzo Librandi, Dec 30 2011 *)

CROSSREFS

Cf. A046852, A002385.

Sequence in context: A118491 A088257 A058694 * A136351 A071290 A185693

Adjacent sequences:  A046850 A046851 A046852 * A046854 A046855 A046856

KEYWORD

nonn,base,easy

AUTHOR

G. L. Honaker, Jr.

EXTENSIONS

More terms from Erich Friedman, Jun 03 2001

STATUS

approved

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Last modified January 22 22:38 EST 2018. Contains 298093 sequences.