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A178767 Values of gcd(Fibonacci(n), Fibonacci(n+3)+2) sorted with no repeats.

%I A178767 #19 Oct 27 2019 05:09:41
%S A178767 1,2,3,4,5,7,13,36,47,68,89,123,233,644,843,1220,1597,2207,4181,11556,
%T A178767 15127,21892,28657,39603,75025,207364,271443,392836,514229,710647,
%U A178767 1346269,3720996,4870847,7049156,9227465,12752043,24157817,66770564,87403803,126491972
%N A178767 Values of gcd(Fibonacci(n), Fibonacci(n+3)+2) sorted with no repeats.
%H A178767 Alois P. Heinz, <a href="/A178767/b178767.txt">Table of n, a(n) for n = 1..1000</a>
%F A178767 G.f.: (2*x^14 + 3*x^12 + x^11 + 4*x^10 + 7*x^9 + 5*x^7 - 7*x^6 - 5*x^5 - 4*x^4 - 3*x^3 - 2*x^2 - x) / (-x^12 + 18*x^6 - 1). - _Alois P. Heinz_, Dec 29 2010
%p A178767 a:= proc(n) local l, r;
%p A178767       l:= [1, 2, 3, 4, 5, 7, 13, 36, 47, 68, 89, 123, 233, 644];
%p A178767       `if`(n<15, l[n], (<<0|1>, <-1|18>> ^iquo(n-3, 6, 'r').
%p A178767                         <<l[3+r], l[9+r]>>) [1,1])
%p A178767     end:
%p A178767 seq(a(n), n=1..40);  # _Alois P. Heinz_, Dec 29 2010
%t A178767 Take[Union@Table[GCD[Fibonacci[n],Fibonacci[n+3]+2],{n,1000}],60]
%Y A178767 Cf. A063726, A178766, A134493, A134497, A000045.
%K A178767 nonn
%O A178767 1,2
%A A178767 _Vladimir Joseph Stephan Orlovsky_, Dec 26 2010