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 A362353 #17 Aug 02 2023 13:49:21 %S A362353 1,-3,4,9,-32,25,-27,192,-375,216,81,-1024,3750,-5184,2401,-243,5120, %T A362353 -31250,77760,-84035,32768,729,-24576,234375,-933120,1764735,-1572864, %U A362353 531441,-2187,114688,-1640625,9797760,-28824005,44040192,-33480783,10000000,6561,-524288,10937500,-94058496,403536070,-939524096,1205308188,-800000000,214358881 %N A362353 Triangle read by rows: T(n,k) = (-1)^(n-k)*binomial(n, k)*(k+3)^n, for n >= 0, and k = 0,1, ..., n. Coefficients of certain Sidi polynomials. %C A362353 This is the member N = 2 of a family of signed triangles with row sums n! = A000142(n): T(N; n, k) = (-1)^(n-k)*binomial(n, k)*(k + N + 1)^n, for integer N, n >= 0 and k = 0, 1, ..., n. The row polynomials PS(N; n, z) = Sum_{k=0..n} T(N; n, k)*z^k = ((-1)^n/z^N)*D_{n,N+1,n}(z) in [Sidi 1980]. %C A362353 For N = -1, 0 and 1 see A258773(n, k), A075513(n+1, k) and (-1)^(n-k) * A154715(n, k), respectively. %C A362353 The column sequences, for k = 0, 1, ..., 6 and n >= k, are A141413(n+2), (-1)^(n+1)*A018215(n) = 4*(-1)^(n+1)*A002697(n), 5^2*(-1)^n*A081135(n), (-1)^(n+1)*A128964(n-1) = 6^3*(-1)^(n+1)*A081144(n), 7^4*(-1)^n*A139641(n-4), 2^15*(-1)^(n+1)*A173155(n-5), 3^12*(-1)^n*A173191(n-6), respectively. %C A362353 The e.g.f. of the triangle (see below) needs the exponential convolution (LambertW(-z)/(-z))^2 = Sum_{n>=0} c(2; n)*z^n/n!, where c(2; n) = Sum_{m=0..n} |A137352(n+1, m)|*2^m = A007334(n+2). %C A362353 The row sums give n! = A000142(n). %H A362353 Paolo Xausa, <a href="/A362353/b362353.txt">Table of n, a(n) for n = 0..5049</a> (rows 0..100 of the triangle, flattened) %H A362353 Wolfdieter Lang, <a href="/A075513/a075513.pdf">On a Certain Family of Sidi Polynomials</a>, May 2023. %H A362353 Avram Sidi, <a href="https://doi.org/10.1090/S0025-5718-1980-0572861-2">Numerical Quadrature and Nonlinear Sequence Transformations; Unified Rules for Efficient Computation of Integrals with Algebraic and Logarithmic Endpoint Singularities</a>, Math. Comp., 35 (1980), 851-874. %F A362353 T(n, k) = (-1)^(n-k)*binomial(n, k)*(k + 3)^n, for n >= 0, k = 0, 1, ..., n. %F A362353 O.g.f. of column k: (x*(k + 3))^k/(1 - (k + 3)*x)^(k+1), for k >= 0. %F A362353 E.g.f. of column k: exp(-(k + 3)*x)*((k + 3)*x)^k/k!, for k >= 0. %F A362353 E.g.f. of the triangle, that is, the e.g.f. of its row polynomials {PS(2;n,y)}_{n>=0}): ES(2;y,x) = exp(-3*x)*(1/3)*(d/dz)(W(-z)/(-z))^2, after replacing z by x*y*exp(-x), where W is the Lambert W-function for the principal branch. This becomes ES(2;y,x) = exp(-3*x)*exp(3*(-W(-z)))/(1 - (-W(-z)), with z = x*y*exp(-x). %e A362353 The triangle T begins: %e A362353 n\k 0 1 2 3 4 5 6 7 %e A362353 0: 1 %e A362353 1: -3 4 %e A362353 2: 9 -32 25 %e A362353 3: -27 192 -375 216 %e A362353 4: 81 -1024 3750 -5184 2401 %e A362353 5: -243 5120 -31250 77760 -84035 32768 %e A362353 6: 729 -24576 234375 -933120 1764735 -1572864 531441 %e A362353 7: -2187 114688 -1640625 9797760 -28824005 44040192 -33480783 10000000 %e A362353 ... %e A362353 n = 8: 6561 -524288 10937500 -94058496 403536070 -939524096 1205308188 -800000000 2143588, %e A362353 n = 9: -19683 2359296 -70312500 846526464 -5084554482 16911433728 -32543321076 36000000000 -21221529219 5159780352. %t A362353 A362353row[n_]:=Table[(-1)^(n-k)Binomial[n,k](k+3)^n,{k,0,n}];Array[A362353row,10,0] (* _Paolo Xausa_, Jul 30 2023 *) %Y A362353 Cf. A000142 (row sums), A075513, A154715, A258773. %Y A362353 Columns k = 0..6 involve (see above): A002697, A007334, A018215, A081135, A081144, A128964, A137352, A139641, A141413, A173155, A173191. %K A362353 sign,tabl,easy %O A362353 0,2 %A A362353 _Harlan J. Brothers_ and _Wolfdieter Lang_, Apr 27 2023 %E A362353 a(41)-a(44) from _Paolo Xausa_, Jul 31 2023