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A081831
a(1)=a(2)=1, a(n) = a(a(n - a(n-1))) + a(n - a(n-2)).
7
1, 1, 2, 3, 3, 3, 5, 4, 5, 5, 5, 8, 6, 6, 8, 8, 8, 8, 8, 12, 9, 8, 10, 11, 11, 12, 12, 12, 12, 12, 12, 20, 12, 10, 15, 17, 16, 13, 18, 16, 15, 20, 17, 19, 20, 20, 20, 20, 20, 20, 20, 32, 17, 16, 21, 24, 25, 18, 18, 32, 25, 20, 21, 27, 25, 26, 28, 28, 23, 32, 28, 24, 32, 32, 25, 31
OFFSET
1,3
LINKS
FORMULA
Conjecture: a(n)/n -> C = 0.2....
MAPLE
a:= proc(n) option remember: if n<3 then 1 else procname(procname(n-procname(n-1)))+ procname(n-procname(n-2)) fi end: seq(a(n), n=1..80); # Muniru A Asiru, Jun 04 2018
MATHEMATICA
a[1]=a[2]=1; a[n_]:=a[n]=a[a[n-a[n-1]]]+a[n-a[n-2]]; Table[a[n], {n, 80}] (* Harvey P. Dale, Aug 04 2019 *)
PROG
(GAP) a:=[1, 1];; for n in [3..80] do a[n]:=a[a[n-a[n-1]]]+a[n-a[n-2]]; od; a; # Muniru A Asiru, Jun 04 2018
CROSSREFS
Cf. A005185.
Sequence in context: A213617 A205778 A328972 * A349837 A111912 A096288
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Apr 10 2003
STATUS
approved