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A096870
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Difference between the n-th repunit and the previous prime.
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3
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4, 2, 2, 18, 2, 20, 10, 2, 14, 52, 8, 18, 58, 58, 72, 4, 20, 74, 84, 58, 14, 18, 82, 168, 28, 50, 168, 84, 8, 138, 112, 82, 2, 28, 2, 62, 34, 50, 74, 24, 8, 54, 204, 22, 428, 40, 118, 200, 72, 40, 30, 42, 284, 44, 114, 268, 80, 18, 4, 74, 142, 182, 140, 112, 214, 152, 90
(list; graph; refs; listen; history; internal format)
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OFFSET
| 2,1
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FORMULA
| a(n) = A002275(n) - A096498(n) = A096499(n) - A096869(n).
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MATHEMATICA
| PrevPrim[n_] := Block[{k = n - 1}, While[ !PrimeQ[k], k-- ]; k]; Table[(10^n - 1)/9 - PrevPrim[(10^n - 1)/9], {n, 2, 70}]
Table[With[{ru=(10^n-1)/9}, ru-NextPrime[ru, -1]], {n, 2, 70}] (* From Harvey P. Dale, Aug 14 2011 *)
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CROSSREFS
| Cf. A096869.
Sequence in context: A136202 A075418 A199221 * A134977 A199081 A145326
Adjacent sequences: A096867 A096868 A096869 * A096871 A096872 A096873
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KEYWORD
| nonn
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AUTHOR
| Robert G. Wilson v (rgwv(AT)rgwv.com), Jul 12 2004
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