A293472 Triangle read by rows, coefficients of polynomials in t = log(x) of the n-th derivative of x^x, evaluated at x = 1. T(n, k) with n >= 0 and 0 <= k <= n.
1, 1, 1, 2, 2, 1, 3, 6, 3, 1, 8, 12, 12, 4, 1, 10, 40, 30, 20, 5, 1, 54, 60, 120, 60, 30, 6, 1, -42, 378, 210, 280, 105, 42, 7, 1, 944, -336, 1512, 560, 560, 168, 56, 8, 1, -5112, 8496, -1512, 4536, 1260, 1008, 252, 72, 9, 1
Offset: 0
Examples
Triangle starts: 0: [ 1] 1: [ 1, 1] 2: [ 2, 2, 1] 3: [ 3, 6, 3, 1] 4: [ 8, 12, 12, 4, 1] 5: [ 10, 40, 30, 20, 5, 1] 6: [ 54, 60, 120, 60, 30, 6, 1] 7: [-42, 378, 210, 280, 105, 42, 7, 1] ... For n = 3, the 3rd derivative of x^x is p(3,x,t) = x^x*t^3 + 3*x^x*t^2 + 3*x^x*t + x^x + 3*x^x*t/x + 3*x^x/x - x^x/x^2 where log(x) is substituted by t. Evaluated at x = 1: p(3,1,t) = 3 + 6*t + 3*t^2 + t^3 with coefficients [3, 6, 3, 1].
Crossrefs
Programs
-
Maple
dx := proc(m, n) if n = 0 then return [1] fi; subs(ln(x) = t, diff(x^(x^m), x$n)): subs(x = 1, %): PolynomialTools:-CoefficientList(%,t) end: ListTools:-Flatten([seq(dx(1, n), n=0..10)]);
-
Mathematica
dx[m_, n_] := ReplaceAll[CoefficientList[ReplaceAll[Expand[D[x^x^m, {x, n}]], Log[x] -> t], t], x -> 1]; Table[dx[1, n], {n, 0, 7}] // Flatten