This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A367299 #18 Mar 28 2025 04:35:50 %S A367299 1,2,5,5,18,24,12,62,126,115,29,192,545,794,551,70,567,2040,4114,4716, %T A367299 2640,169,1618,7047,17940,28420,26964,12649,408,4508,23020,70582, %U A367299 140988,185122,150122,60605,985,12336,72222,258492,620379,1027368,1156155,819558,290376 %N A367299 Triangular array T(n,k), read by rows: coefficients of strong divisibility sequence of polynomials p(1,x) = 1, p(2,x) = 2 + 5*x, p(n,x) = u*p(n-1,x) + v*p(n-2,x) for n >= 3, where u = p(2,x), v = 1 - 2*x - x^2. %C A367299 Because (p(n,x)) is a strong divisibility sequence, for each integer k, the sequence (p(n,k)) is a strong divisibility sequence of integers. %H A367299 Rigoberto Flórez, Robinson Higuita, and Antara Mukherjee, <a href="http://math.colgate.edu/~integers/s14/s14.Abstract.html">Characterization of the strong divisibility property for generalized Fibonacci polynomials</a>, Integers, 18 (2018), Paper No. A14. %F A367299 p(n,x) = u*p(n-1,x) + v*p(n-2,x) for n >= 3, where p(1,x) = 1, p(2,x) = 2 + 5*x, u = p(2,x), and v = 1 - 2*x - x^2. %F A367299 p(n,x) = k*(b^n - c^n), where k = -(1/sqrt(8 + 12*x + 21*x^2)), b = (1/2) (5*x + 2 + 1/k), c = (1/2) (5*x + 2 - 1/k). %e A367299 First eight rows: %e A367299 1 %e A367299 2 5 %e A367299 5 18 24 %e A367299 12 62 126 115 %e A367299 29 192 545 794 551 %e A367299 70 567 2040 4114 4716 2640 %e A367299 169 1618 7047 17940 28420 26964 12649 %e A367299 408 4508 23020 70582 140988 185122 150122 60605 %e A367299 Row 4 represents the polynomial p(4,x) = 12 + 62*x + 126*x^2 + 115*x^3, so (T(4,k)) = (12,62,126,115), k=0..3. %t A367299 p[1, x_] := 1; p[2, x_] := 2 + 5 x; u[x_] := p[2, x]; v[x_] := 1 - 2 x - x^2; %t A367299 p[n_, x_] := Expand[u[x]*p[n - 1, x] + v[x]*p[n - 2, x]] %t A367299 Grid[Table[CoefficientList[p[n, x], x], {n, 1, 10}]] %t A367299 Flatten[Table[CoefficientList[p[n, x], x], {n, 1, 10}]] %Y A367299 Cf. A000129 (column 1); A004254 (p(n,n-1)); A186446 (row sums, p(n,1)); A007482 (alternating row sums, p(n,-1)); A041025 (p(n,-2)); A094440, A367208, A367209, A367210, A367211, A367297, A367298, A367300. %K A367299 nonn,tabl %O A367299 1,2 %A A367299 _Clark Kimberling_, Dec 23 2023