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A052012 Number of primes between successive Lucas numbers. 4
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; text; internal format)
OFFSET

1,5

LINKS

Table of n, a(n) for n=1..41.

EXAMPLE

Between Luc(7)=29 and Luc(8)=47 we find the following primes: 31, 37, 41 and 43 hence a(7)=4.

MATHEMATICA

PrimePi[Last[#]-1]-PrimePi[First[#]]&/@Partition[LucasL[ Range[45]], 2, 1] (* Harvey P. Dale, Jun 28 2011 *)

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

CROSSREFS

Cf. A000204, A052011.

Cf. A010051.

Sequence in context: A025049 A293552 A293546 * A234961 A018061 A304778

Adjacent sequences:  A052009 A052010 A052011 * A052013 A052014 A052015

KEYWORD

nonn,nice

AUTHOR

Patrick De Geest, Nov 15 1999

STATUS

approved

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Last modified May 9 00:09 EDT 2021. Contains 343685 sequences. (Running on oeis4.)