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 A316659 #12 May 02 2021 06:27:59 %S A316659 0,0,0,1,0,1,2,1,0,5,8,3,0,16,30,16,2,0,45,104,81,24,2,0,121,340,356, %T A316659 170,35,2,0,320,1068,1411,932,315,48,2,0,841,3262,5209,4396,2079,532, %U A316659 63,2,0,2205,9760,18281,18784,11440,4144,840,80,2,0,5776,28746 %N A316659 Irregular triangle read by rows: row n consists of the coefficients in the expansion of the polynomial x*(x^2 - 2) + x*(((v - w)/2)^n + ((v + w)/2)^n), where v = 3 + 2*x and w = sqrt(5 + 4*x). %C A316659 The triangle is related to the Kauffman bracket polynomial for the Turk's Head Knot ((3,n)-torus knot). Column 1 matches the determinant of the Turk's Head Knots THK(3,k) A004146. %H A316659 Louis H. Kauffman, <a href="https://doi.org/10.1090/S0002-9947-1990-0958895-7 ">An invariant of regular isotopy</a>, Trans. Amer. Math. Soc., Vol. 318 (1990), 417-471. %H A316659 Seong Ju Kim, R. Stees, and L. Taalman, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL19/Stees/stees4.html">Sequences of Spiral Knot Determinants</a>, Journal of Integer Sequences, Vol. 19 (2016), #16.1.4. %H A316659 Alexander Stoimenow, <a href="http://dx.doi.org/10.4310/CAG.2005.v13.n3.a5">Square numbers, spanning trees and invariants of achiral knots</a>, Communications in Analysis and Geometry, Vol. 13 (2005), 591-631. %F A316659 T(n,1) = A004146(n). %F A316659 T(n,2) = A122076(n,1) = A099920(2*n-1). %F A316659 G.f.: (x^3 - 2*x)/(1 - y) + (2*x - 3*x*y - 2*x^2*y)/(1 - 3*y - 2*x*y + y^2 + 2*x*y^2 + x^2*y^2). %e A316659 The triangle T(n,k) begins: %e A316659 n\k: 0 1 2 3 4 5 6 7 8 9 10 11 %e A316659 0: 0 0 0 1 %e A316659 1: 0 1 2 1 %e A316659 2: 0 5 8 3 %e A316659 3: 0 16 30 16 2 %e A316659 4: 0 45 104 81 24 2 %e A316659 5: 0 121 340 356 170 35 2 %e A316659 6: 0 320 1068 1411 932 315 48 2 %e A316659 7: 0 841 3262 5209 4396 2079 532 63 2 %e A316659 8: 0 2205 9760 18281 18784 11440 4144 840 80 2 %e A316659 9: 0 5776 28746 61786 74838 55809 26226 7602 1260 99 2 %e A316659 10: 0 15125 83620 202841 282980 249815 144488 54690 13080 1815 120 2 %e A316659 ... %t A316659 v = 3 + 2*x; w = Sqrt[5 + 4*x]; %t A316659 row[n_] := CoefficientList[x*(x^2 - 2) + x*(((v - w)/2)^n + ((v + w)/2)^n), x]; %t A316659 Array[row, 15, 0] // Flatten %o A316659 (Maxima) %o A316659 v : 3 + 2*x$ w : sqrt(5 + 4*x)$ %o A316659 p(n, x) := expand(x*(x^2 - 2) + x*(((v - w)/2)^n + ((v + w)/2)^n))$ %o A316659 for n:0 thru 15 do print(makelist(ratcoef(p(n, x), x, k), k, 0, max(3, n + 1))); %Y A316659 Row sums: A000302 (Powers of 4). %Y A316659 Row 1: row 1 of A300184, A300192 and row 0 of A300454. %Y A316659 Row 2: row 2 of A300454. %Y A316659 Cf. A137396, A299989, A300453. %K A316659 nonn,tabf %O A316659 0,7 %A A316659 _Franck Maminirina Ramaharo_, Jul 09 2018