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 A330209 #16 Aug 23 2023 12:22:37 %S A330209 1,2,1,2,5,1,12,9,1,12,39,14,1,90,95,20,1,90,375,195,27,1,840,1155, %T A330209 357,35,1,840,4305,2940,602,44,1,9450,16065,6552,954,54,1,9450,57645, %U A330209 48825,13230,1440,65,1,124740,252945,128205,24750,2090,77,1,124740,883575,893970,301455,43560,2937,90,1 %N A330209 Nonzero coefficients of the polynomials (x + d/dx)^n x^2, in row-major order. %C A330209 The similar-looking polynomials (x-d/dx)^n * 1 are the probabilist's Hermite polynomials, A096713. %H A330209 Robert S. Maier, <a href="https://arxiv.org/abs/2308.10332">Boson Operator Ordering Identities from Generalized Stirling and Eulerian Numbers</a>, arXiv:2308.10332 [math.CO], 2023. See p. 19. %e A330209 x^2 ; 2x + x^3; 2 + 5x^2 + x^4; 12x + 9x^3 + x^5. %Y A330209 Cf. A096713. %K A330209 nonn,tabf %O A330209 0,2 %A A330209 _Chris Jones_, Dec 05 2019