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A054268
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Sum of composite numbers between prime p and nextprime(p) is a repdigit.
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9
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OFFSET
| 0,1
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COMMENTS
| No additional terms below 472882027
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LINKS
| Eric Weisstein's World of Mathematics, Repdigit
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EXAMPLE
| a(5) is ok since between 259259257 and nextprime 259259261 we get the sum 259259258 + 259259259 + 259259260 which yield repdigit 777777777.
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MATHEMATICA
| repQ[n_]:=Count[DigitCount[n], 0]==9; Select[Prime[Range[2, 14500000]], repQ[Total[Range[#+1, NextPrime[#]-1]]]&] [From Harvey P. Dale, Jan 29 2011]
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CROSSREFS
| Cf. A010785, A028987, A028988, A046933, A054264, A054265, A054266, A054267.
Sequence in context: A003112 A130187 A054266 * A153137 A105526 A070743
Adjacent sequences: A054265 A054266 A054267 * A054269 A054270 A054271
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KEYWORD
| nonn,base,hard
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AUTHOR
| Patrick De Geest (pdg(AT)worldofnumbers.com), Apr 15 2000.
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