A079878 a(1)=1, then a(n)=2*a(n-1) if 2*a(n-1)<=n, a(n)=2*a(n-1)-n otherwise.
1, 2, 1, 2, 4, 2, 4, 8, 7, 4, 8, 4, 8, 2, 4, 8, 16, 14, 9, 18, 15, 8, 16, 8, 16, 6, 12, 24, 19, 8, 16, 32, 31, 28, 21, 6, 12, 24, 9, 18, 36, 30, 17, 34, 23, 46, 45, 42, 35, 20, 40, 28, 3, 6, 12, 24, 48, 38, 17, 34, 7, 14, 28, 56, 47, 28, 56, 44, 19, 38, 5, 10, 20, 40, 5, 10, 20, 40, 1, 2
Offset: 1
Keywords
Links
- Reinhard Zumkeller, Table of n, a(n) for n = 1..10000
Programs
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Haskell
a079878 n = a079878_list !! (n-1) a079878_list = 1 : zipWith (\x n -> if x <= n then x else x - n) (map (* 2) a079878_list) [2..] -- Reinhard Zumkeller, Nov 13 2011 -
Mathematica
nxt[{n_,a_}]:={n+1,If[2a<=n+1,2a,2a-n-1]}; Transpose[NestList[nxt,{1,1},80]][[2]] (* Harvey P. Dale, Jul 20 2015 *) -
PARI
a=1; for(n=2,100,b=if(sign(2*a-n)-1,2*a,2*a-n); a=b; print1(b,","))
Formula
a(n) = A064434(n)+1.
It seems that sum(k=1, n, a(k))/n^2 ->1/4
Comments