Coefficients of expansion of 1/sqrt(1 - 10*x + 9*x^2); also, a(n) is the central coefficient of (1 + 5*x + 4*x^2)^n.

A084771

Coefficients of expansion of 1/sqrt(1 - 10*x + 9*x^2); also, a(n) is the central coefficient of (1 + 5*x + 4*x^2)^n.

Terms

    a(0) =1a(1) =5a(2) =33a(3) =245a(4) =1921a(5) =15525a(6) =127905a(7) =1067925a(8) =9004545a(9) =76499525a(10) =653808673a(11) =5614995765a(12) =48416454529a(13) =418895174885

External references