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%I #34 May 28 2014 23:04:13
%S 0,1,1,2,2,4,6,10,16,18,24,42,66,108,120,228,348,576,720,1296,2016,
%T 3312,5256,7200,12456,17860,25200,40256,37368,39600,72900,112500,
%U 185400,282204,364800,517600,805392,1133988,1939380,2788176,4727556,6819120
%N a(n) = phi( a(n-1) + a(n-2) + 1) with a(0) = 0 and a(1) = 1.
%C Difference between A000045 & A228807: 0, 0, 0, 0, 1, 1, 2, 3, 5, 16, 31, 47, 78, 125, 257, 382, 639, 1021, 1864, 2885, 4749, 7634, ... .
%H Mihai Caragiu and Robert G. Wilson v, <a href="/A228807/b228807.txt">Table of n, a(n) for n = 0..500</a>
%H Mihai Caragiu, <a href="http://mihai-caragiu-maths.blogspot.com/2010/10/phi-bonacci-sequence-update.html">Mathematical Trips</a>.
%H Mihai Caragiu and Ashley Risch, <a href="http://www.pphmj.com/abstract/5828.htm">An Euler-Fibonacci Sequence</a>, Far East Journal of Mathematical Sciences 52 (1), 1 - 7 (May 2011)
%F a(n) = phi( a(n-1) + a(n-2) + 1) with a(0) = 0 & a(1) = 1.
%t a[0] = 0; a[1] = 1; a[n_] := a[n] = EulerPhi[a[n - 1] + a[n - 2] + 1]; Array[a, 50, 0]
%t RecurrenceTable[{a[0]==0,a[1]==1,a[n]==EulerPhi[a[n-1]+a[n-2]+1]},a,{n,50}] (* _Harvey P. Dale_, Feb 16 2014 *)
%Y Cf. A000010, A000045.
%K nonn
%O 0,4
%A _Mihai Caragiu_ and _Robert G. Wilson v_, Sep 04 2013
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