OFFSET
1,2
COMMENTS
The fractal nature of the sequence is emphasized in the scatterplot of a(n) - n (see Links section). - Rémy Sigrist, Nov 26 2017
LINKS
Rémy Sigrist, Table of n, a(n) for n = 1..25000
Rémy Sigrist, Scatterplot of (n, a(n)-n) for n=1..25000
EXAMPLE
For a(4)..a(19) we have that: 2+3=5, 1+3=4, 3+5=8, 2+5=7, 5+4=9, 3+4=7, 4+8=12, 5+8=13, 8+7=15, 4+7=11, 7+9=16, 8+9=17, 9+7=16, 7+7=14, 7+12=19, 9+12=21.
MATHEMATICA
Fold[Append[#1, If[EvenQ[#2], #1[[#2]] + #1[[#2 + 1]] & @@ {#1, #2/2}, #1[[#2]] + #1[[#2 - 2]] & @@ {#1, (#2 + 1)/2}]] &, Range@ 3, Range[4, 82]] (* Michael De Vlieger, Nov 26 2017 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Martin Michael Musatov, Oct 02 2017
EXTENSIONS
Better definition, corrected and extended by Omar E. Pol, Oct 03 2017
STATUS
approved