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%I #23 Dec 05 2021 00:18:34
%S 759135467284,74074527465,833209994749,907284522214,1740494516963,
%T 2647779039177,4388273556140,7036052595317,11424326151457,
%U 18460378746774,29884704898231,48345083645005,78229788543236,126574872188241,204804660731477,331379532919718,536184193651195
%N Fibonacci-like sequence of composite numbers with a(0) = 759135467284, a(1) = 74074527465.
%C This is a second-order linear recurrence sequence with a(0) and a(1) coprime that does not contain any primes.
%C This sequence was found using Knuth's method.
%H R. L. Graham, <a href="http://www.jstor.org/stable/2689243">A Fibonacci-Like sequence of composite numbers</a>, Math. Mag., Vol. 37, No. 5 (1964), pp. 322-324.
%H Donald E. Knuth, <a href="http://www.jstor.org/stable/2691504">A Fibonacci-Like sequence of composite numbers</a>, Math. Mag., Vol. 63, No. 1 (1990), pp. 21-25.
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (1,1).
%F a(n) = a(n-1) + a(n-2).
%p a:= n-> (<<0|1>, <1|1>>^n. <<759135467284, 74074527465>>)[1, 1]:
%p seq(a(n), n=0..16); # _Alois P. Heinz_, Oct 06 2021
%t LinearRecurrence[{1, 1}, {759135467284, 74074527465}, 17] (* _Amiram Eldar_, Oct 07 2021 *)
%o (PARI) a(n)=759135467284*fibonacci(n-1)+ 74074527465*fibonacci(n)
%Y Cf. A221286, A083104, A082411, A083105, A083216, A083216.
%K nonn,easy
%O 0,1
%A _Chittaranjan Pardeshi_, Oct 06 2021