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 A292604 #29 Mar 06 2020 04:05:17 %S A292604 1,1,0,5,1,0,61,28,1,0,1385,1011,123,1,0,50521,50666,11706,506,1,0, %T A292604 2702765,3448901,1212146,118546,2041,1,0,199360981,308869464, %U A292604 147485535,24226000,1130235,8184,1,0 %N A292604 Triangle read by rows, coefficients of generalized Eulerian polynomials F_{2}(x). %C A292604 The generalized Eulerian polynomials F_{m}(x) are defined F_{m; 0}(x) = 1 for all m >= 0 and for n > 0: %C A292604 F_{0; n}(x) = Sum_{k=0..n} A097805(n, k)*(x-1)^(n-k) with coeffs. in A129186. %C A292604 F_{1; n}(x) = Sum_{k=0..n} A131689(n, k)*(x-1)^(n-k) with coeffs. in A173018. %C A292604 F_{2; n}(x) = Sum_{k=0..n} A241171(n, k)*(x-1)^(n-k) with coeffs. in A292604. %C A292604 F_{3; n}(x) = Sum_{k=0..n} A278073(n, k)*(x-1)^(n-k) with coeffs. in A292605. %C A292604 F_{4; n}(x) = Sum_{k=0..n} A278074(n, k)*(x-1)^(n-k) with coeffs. in A292606. %C A292604 The case m = 1 are the Eulerian polynomials whose coefficients are the Eulerian numbers which are displayed in Euler's triangle A173018. %C A292604 Evaluated at x in {-1, 1, 0} these families of polynomials give for the first few m: %C A292604 F_{m} : F_{0} F_{1} F_{2} F_{3} F_{4} %C A292604 x = -1: A165326 A155585 A002105 A292609 A292607 %C A292604 x = 1: A000012 A000142 A000680 A014606 A014608 ... (m*n)!/m!^n %C A292604 x = 0: -- A000012 A000364 A002115 A211212 ... m-alternating permutations of length m*n. %C A292604 Note that the constant terms of the polynomials are the generalized Euler numbers as defined in A181985. In this sense generalized Euler numbers are also generalized Eulerian numbers. %D A292604 G. Frobenius. Über die Bernoullischen Zahlen und die Eulerschen Polynome. Sitzungsber. Preuss. Akad. Wiss. Berlin, pages 200-208, 1910. %F A292604 F_{2; n}(x) = Sum_{k=0..n} A241171(n, k)*(x-1)^(n-k) for n>0 and F_{2; 0}(x) = 1. %e A292604 Triangle starts: %e A292604 [n\k][ 0 1 2 3 4 5 6] %e A292604 -------------------------------------------------- %e A292604 [0][ 1] %e A292604 [1][ 1, 0] %e A292604 [2][ 5, 1, 0] %e A292604 [3][ 61, 28, 1, 0] %e A292604 [4][ 1385, 1011, 123, 1, 0] %e A292604 [5][ 50521, 50666, 11706, 506, 1, 0] %e A292604 [6][2702765, 3448901, 1212146, 118546, 2041, 1, 0] %p A292604 Coeffs := f -> PolynomialTools:-CoefficientList(expand(f), x): %p A292604 A292604_row := proc(n) if n = 0 then return [1] fi; %p A292604 add(A241171(n, k)*(x-1)^(n-k), k=0..n); [op(Coeffs(%)), 0] end: %p A292604 for n from 0 to 6 do A292604_row(n) od; %t A292604 T[n_, k_] /; 1 <= k <= n := T[n, k] = k (2 k - 1) T[n - 1, k - 1] + k^2 T[n - 1, k]; T[_, 1] = 1; T[_, _] = 0; %t A292604 F[2, 0][_] = 1; F[2, n_][x_] := Sum[T[n, k] (x - 1)^(n - k), {k, 0, n}]; %t A292604 row[n_] := If[n == 0, {1}, Append[CoefficientList[ F[2, n][x], x], 0]]; %t A292604 Table[row[n], {n, 0, 7}] (* _Jean-François Alcover_, Jul 06 2019 *) %o A292604 (Sage) %o A292604 def A292604_row(n): %o A292604 if n == 0: return [1] %o A292604 S = sum(A241171(n, k)*(x-1)^(n-k) for k in (0..n)) %o A292604 return expand(S).list() + [0] %o A292604 for n in (0..6): print(A292604_row(n)) %Y A292604 F_{0} = A129186, F_{1} = A173018, F_{2} is this triangle, F_{3} = A292605, F_{4} = A292606. %Y A292604 First column: A000364. Row sums: A000680. Alternating row sums: A002105. %Y A292604 Cf. A181985, A241171. %K A292604 nonn,tabl %O A292604 0,4 %A A292604 _Peter Luschny_, Sep 20 2017