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 A073445 Second differences of A002808, the sequence of composites. 3
 0, -1, 0, 1, 0, -1, 0, 1, 0, -1, 0, 1, -1, 0, 0, 0, 1, 0, -1, 0, 0, 0, 1, -1, 0, 1, 0, -1, 0, 1, -1, 0, 0, 0, 1, -1, 0, 0, 0, 1, 0, -1, 0, 0, 0, 1, -1, 0, 1, 0, -1, 0, 0, 0, 1, -1, 0, 1, -1, 0, 0, 0, 1, -1, 0, 0, 0, 0, 0, 1, -1, 0, 1, 0, -1, 0, 1, 0, -1, 0, 1, -1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, -1, 0, 1, -1, 0, 0, 0, 1, 0, -1, 0, 0, 0, 0, 0, 0, 0, 1, 0, -1, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS Reinhard Zumkeller, Table of n, a(n) for n = 1..10000 FORMULA a(n)=c[n+2]-2c[n+1])+c[n], where c(n)=A002808(n). a(n) = A073783(n+1) - A073783(n). - Reinhard Zumkeller, Jan 10 2013 MATHEMATICA c[x_] := FixedPoint[x+PrimePi[ # ]+1&, x] Table[(c[w+2]-2*c[w+1])+c[w]), {w, 1, 1000}] PROG (Haskell) a073445 n = a073445_list !! (n-1) a073445_list = zipWith (-) (tail a073783_list) a073783_list -- Reinhard Zumkeller, Jan 10 2013 CROSSREFS Also first differences of A054546. Cf. A002808, A054546. Sequence in context: A188510 A131734 A134452 * A179081 A113217 A147781 Adjacent sequences:  A073442 A073443 A073444 * A073446 A073447 A073448 KEYWORD sign AUTHOR Labos Elemer, Aug 01 2002 STATUS approved

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Last modified October 15 14:07 EDT 2018. Contains 316236 sequences. (Running on oeis4.)