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A047846 Number of successive odd nonprimes (A014076). 6
1, 1, 1, 1, 2, 2, 1, 1, 2, 2, 2, 1, 2, 1, 2, 3, 1, 1, 1, 6, 1, 2, 4, 2, 2, 1, 2, 2, 4, 1, 5, 5, 1, 1, 2, 4, 2, 2, 2, 2, 1, 4, 6, 1, 1, 6, 2, 4, 1, 2, 3, 2, 2, 1, 2, 3, 1, 3, 4, 4, 2, 1, 2, 3, 1, 1, 5, 3, 1, 3, 1, 2, 5, 8, 2, 4, 2, 2, 2, 4, 2, 2, 2, 2, 1, 5 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,5

COMMENTS

Beginning with a(2), length of n-th run of identical numbers in A160522 [Kyle Stern, Jun 19 2009]

a(n+1) = A196277(n+1) - A196277(n). [Reinhard Zumkeller, Sep 30 2011]

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

MATHEMATICA

Length /@ Split[Select[Range[1, 629, 2], PrimeOmega[#] != 1 &], #2 - #1 <= 2 &] (* Jayanta Basu, Aug 11 2013 *)

PROG

(Haskell)

a047846 n = a047846_list !! (n-1)

a047846_list = 1 : zipWith (-) (tail a196277_list) a196277_list

-- Reinhard Zumkeller, Sep 30 2011

CROSSREFS

Length of n-th run in A014076.

Cf. A160522.

Sequence in context: A102715 A254687 A182590 * A212632 A025885 A198337

Adjacent sequences:  A047843 A047844 A047845 * A047847 A047848 A047849

KEYWORD

easy,nonn

AUTHOR

Enoch Haga

EXTENSIONS

a(51) and a(84) corrected by Reinhard Zumkeller, Sep 30 2011

STATUS

approved

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Last modified June 6 11:14 EDT 2020. Contains 334827 sequences. (Running on oeis4.)