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 A036073 #44 Aug 14 2021 11:06:40 %S A036073 1,2,1,5,1,6,15,1,11,30,52,1,20,80,150,203,1,37,210,525,780,877,1,70, %T A036073 560,1785,3395,4263,4140,1,135,1526,6125,14140,22288,24556,21147,1, %U A036073 264,4240,21420,58842,109998,150402,149040,115975,1,521,11970,76385,248115 %N A036073 Triangle of coefficients arising in calculation of A002872 and A002874 (sorting numbers). %C A036073 For connection to A002872, A002874, and other columns of A162663, see the formula in A162663. - _Andrey Zabolotskiy_, Oct 25 2017 %D A036073 T. S. Motzkin, Sorting numbers for cylinders and other classification numbers, in Combinatorics, Proc. Symp. Pure Math. 19, AMS, 1971, pp. 167-176. %H A036073 T. S. Motzkin, <a href="/A000262/a000262.pdf">Sorting numbers for cylinders and other classification numbers</a>, in Combinatorics, Proc. Symp. Pure Math. 19, AMS, 1971, pp. 167-176. [Annotated, scanned copy] %H A036073 <a href="/index/So#sorting">Index entries for sequences related to sorting</a> %F A036073 E.g.f.: exp(exp(x*y)+y*(exp(x)-1)-1). %e A036073 Triangle begins: %e A036073 1; %e A036073 . 2; %e A036073 . 1, 5; %e A036073 . 1, 6, 15; %e A036073 . 1, 11, 30, 52; %e A036073 . 1, 20, 80, 150, 203; %e A036073 . 1, 37, 210, 525, 780, 877; %e A036073 ... %p A036073 egf:= exp(exp(x*y)+y*(exp(x)-1)-1): %p A036073 T:= (n, k)-> n!*coeff(series(coeff(series(egf, y, k+1) %p A036073 , y, k), x, n+1), x, n): %p A036073 seq(seq(T(n, k), k=min(n, 1)..n), n=0..10); # _Alois P. Heinz_, Mar 28 2013 %o A036073 (PARI) T(n, k) = { my(y = 'y + 'y*O('y^k), x = 'x + 'x*O('x^n); ); n!*polcoeff(polcoeff(exp(exp(x*y)+y*(exp(x)-1)-1), n, 'x), k, 'y); } %o A036073 for(n=0,10,for(k=0,n,print1(T(n,k),", "));print()); /* print triangle */ %o A036073 \\ _Michel Marcus_, Mar 27 2013 %o A036073 (PARI) listpols(n)= {my(z = t + t*O(t^n)); zp = exp(exp(z)-1+(exp(p*z)-1)/p); for (i=0, n, print(i!*polcoeff(zp, i, t)););} \\ _Michel Marcus_, Mar 27 2013 %Y A036073 Row sums give A001861. %Y A036073 Diagonal gives A000110(n+1) - _Alois P. Heinz_, Mar 27 2013 %Y A036073 Cf. A162663. %K A036073 nonn,tabf %O A036073 0,2 %A A036073 _N. J. A. Sloane_ %E A036073 Edited by _Vladeta Jovovic_, Sep 17 2003 %E A036073 Name corrected by _Andrey Zabolotskiy_, Oct 22 2017