%I A011769
%S A011769 1,3,7,19,51,141,393,1107,3139,8955,25675,73945,213825,620595,1807263,
%T A011769 5279283,15465139,45420261,133724757,394494631,1165998951,3452224863,
%U A011769 10236848727,30396848949,90369294541,268957845831,801244711843
%N A011769 a_0 = 1, a_{n+2} = 3 * a_{n+1} - F_n*(F_n + 1), where F_n is n-th Fibonacci 
               number.
%D A011769 L. Euler, (E326) Observationes analyticae, reprinted in: Opera Omnia. 
               Teubner, Leipzig, 1911, Series (1), Vol. 15, p. 59.
%D A011769 R. L. Graham, D. E. Knuth and O. Patashnik, Concrete Mathematics. Addison-Wesley, 
               Reading, MA, 1990, p. 575.
%D A011769 R. K. Guy, The Second Strong Law of Small Numbers [ Math. Mag, 63(1990) 
               3-20, esp. 18-19 ]
%D A011769 P. Henrici, Applied and Computational Complex Analysis. Wiley, NY, 3 
               vols., 1974-1986. (Vol. 1, p. 42.)
%D A011769 V. E. Hoggatt, Jr. and M. Bicknell, Diagonal sums of generalized Pascal 
               triangles, Fib. Quart., 7 (1969), 341-358, 393.
%D A011769 J. Riordan, Combinatorial Identities, Wiley, 1968, p. 74.
%D A011769 L. W. Shapiro et al., The Riordan group, Discrete Applied Math., 34 (1991), 
               229-239.
%D A011769 See also the references mentioned under A002426.
%Y A011769 Cf. A002426.
%Y A011769 Sequence in context: A052948 A026325 A002426 this_sequence A087432 A135052 
               A146597
%Y A011769 Adjacent sequences: A011766 A011767 A011768 this_sequence A011770 A011771 
               A011772
%K A011769 nonn,easy
%O A011769 0,2
%A A011769 N. J. A. Sloane (njas(AT)research.att.com), R. K. Guy