login
a(n)=a(a(n-3))+a(n-a(n-3)) if n>2 otherwise a(n)=1.
0

%I #4 Mar 30 2012 18:51:20

%S 1,1,1,2,3,4,4,5,6,7,8,8,9,10,10,11,12,13,13,14,15,16,16,17,18,19,20,

%T 20,21,22,23,24,24,25,26,26,27,28,29,29,30,31,32,33,34,34,35,36,36,36,

%U 37,38,39,40,41,41,42,43,44,45,46,47,47,48

%N a(n)=a(a(n-3))+a(n-a(n-3)) if n>2 otherwise a(n)=1.

%C a(n)<=n-1; apparently a(n-1)<=a(n)<=a(n-1)+1.

%p a := proc(n) option remember; if n<=2 then 1 else a(a(n-3))+a(n-a(n-3)); fi; end;

%Y Cf. A004001, A005229.

%K easy,nonn

%O 0,4

%A _Henry Bottomley_, Apr 05 2000