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A171481 a(n) = a(a(n-1)) + a(n - a(n-1) - 2) with a(0) = 0, a(1) = a(2) = 1. 1

%I

%S 0,1,1,1,2,2,2,2,3,3,3,3,3,4,5,5,5,5,5,5,6,6,7,7,7,7,7,7,7,8,9,9,9,10,

%T 10,10,10,10,10,10,10,11,11,12,12,12,12,13,14,15,15,15,15,15,15,15,15,

%U 15,16,16,16,17,17,17,17,17,18,18,19,19,20,21,21,21,21,21,21,21,21,21

%N a(n) = a(a(n-1)) + a(n - a(n-1) - 2) with a(0) = 0, a(1) = a(2) = 1.

%C Conjecture 1: a(n) - a(n-1) = 0 or 1.

%C Conjecture 2: lim_{n->infinity} a(n)/n = e/10.

%H Paolo P. Lava, <a href="/A171481/b171481.txt">Table of n, a(n) for n = 0..10000</a>

%p A171481 := proc(n) option remember; if n = 0 then 0; elif n <=2 then 1; else procname(procname(n-1)) +procname(n-procname(n-1)-2) ; end if; end proc: seq(A171481(n),n=0..100) ; # _R. J. Mathar_, Mar 16 2010

%Y Hofstadter-Conway-like sequence (see A004001).

%K nonn

%O 0,5

%A _Jaroslav Krizek_, Dec 09 2009

%E More terms from _R. J. Mathar_, Mar 16 2010

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Last modified September 27 10:28 EDT 2021. Contains 347689 sequences. (Running on oeis4.)