Forbidden subsequences and Chebyshev polynomials
نویسندگان
چکیده
منابع مشابه
Forbidden subsequences and Chebyshev polynomials
In (West, Discrete Math. 157 (1996) 363-374) it was shown using transfer matrices that the number [Sn(123; 3214)1 of permutations avoiding the pattems 123 and 3214 is the Fibonacci number F2, (as are also IS,(213; 1234)1 and 1S~(213;4123)1 ). We now find the transfer matrix for IS , (123;r , r 1 . . . . . 2,1,r + 1)1, IS,(213;1,2 . . . . . r , r + 1)1, and ISn(213;r + 1,1,2 . . . . . r)l, deter...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 1999
ISSN: 0012-365X
DOI: 10.1016/s0012-365x(98)00384-7