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A052012
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Number of primes between successive Lucas numbers.
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4
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1, 0, 1, 0, 2, 2, 4, 6, 9, 15, 20, 31, 48, 72, 110, 170, 257, 400, 608, 950, 1448, 2256, 3487, 5413, 8440, 13118, 20478, 31932, 49995, 78222, 122553, 192262, 301826, 474039, 745772, 1173270, 1848000, 2912623, 4593723, 7249438, 11448047
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,5
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EXAMPLE
| Between Luc(7)=29 and Luc(8)=47 we find the following primes: 31, 37, 41 and 43 hence a(7)=4.
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MATHEMATICA
| PrimePi[Last[#]-1]-PrimePi[First[#]]&/@Partition[LucasL[ Range[45]], 2, 1] (* From Harvey P. Dale, June 28 2011 *)
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PROG
| (Haskell)
a052012 n = a052012_list !! (n-1)
a052012_list = c 1 0 $ tail a000204_list where
c x y ls'@(l:ls) | x < l = c (x+1) (y + a010051 x) ls'
| otherwise = y : c (x+1) 0 ls
-- Reinhard Zumkeller, Dec 18 2011
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CROSSREFS
| Cf. A000204, A052011.
Cf. A010051.
Sequence in context: A058518 A018139 A025049 * A018061 A173495 A166289
Adjacent sequences: A052009 A052010 A052011 * A052013 A052014 A052015
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KEYWORD
| nonn,nice
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AUTHOR
| Patrick De Geest (pdg(AT)worldofnumbers.com), Nov 15 1999.
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