Az Eszterházy Károly Tanárképző Főiskola Tudományos Közleményei. 2004. Sectio Mathematicae. (Acta Academiae Paedagogicae Agriensis : Nova series ; Tom. 31)
MÁTYÁS, F., Genaralize d Fibonacci-type numbers as matrix determinants
42 F. Mátyás Now, we shall deal with the case n > k. If n = k + 1 then 3G- • -<= 4 Pi det (A fc+lxfc+ 1) = det / G1 -e óG 2-k -e 4G 3-k 3 o Pi 0 \ 0 -e k+ 1G 0 0 \ 0 -c*+ 1 0 0 —e" Pi = PiG k + e 3 det / Gi -e 3G 2_* -e 4G 3_ f c -e 3 pi 0 0 -e 3 pi \ 0 0 0 -e kG1 ü \ 0 0 —e ; 0 0 / Developing successively the resulting determinants with respect to their last rows, we have det (A nx n) = PiG k + (e 3)"1 det ( ^ _J + 1 ) = PiG k - e 3 k~ 3e k+ lGi = PiG k + p kG x = G k+ 1. Let us suppose that det (A n_ jX n_j) = G n-j (1 < j < k) holds for an integer n > k + 2. In this case det (A„ x„) = det / Gi -e c 0 V 0 r2 — k = piGn-i + e 3 det Pi (Gi —e v 0 V o • k+ lG 0 0 0 0 _ ek+ 1 0 u 0 _ ek+l '2-k Pi —e" 0 0 0 Gq -e* + 1Gn 0 0 0 0 0 \ 0 0 0 0 -e 3 pi J 0 0\ 0 0 0 0 0/ Now, develop successively the resulting determinants with respect to their last rows. Then one can get the following equalities: k1 det (A n x„) = piG n_i + (e 3) (~e k+ l) G n— piG n-i - e 2G n-k — PiG>j_i + p kG nk — G n. This completes the proof of the Theorem.