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 A060056 #7 May 11 2025 09:14:45 %S A060056 1,40,2016,135680,11977856,1351633920,190346960896,32769353973760, %T A060056 6776471542235136,1658320063181619200,474140484461265944576, %U A060056 156647023437347542794240,59229231136268698009993216,25414555567107834838389882880,12283447443202253774326182445056 %N A060056 Nonzero numbers in expansion of ((tan(x))^4)/4! in (x^n)/n!. %F A060056 a(n) = A059419(4+2*n,4). %o A060056 (PARI) a059419(n, k) = n!*polcoef(tan(x+x*O(x^n))^k/k!, n); %o A060056 a(n) = a059419(2*n+4, 4); \\ _Seiichi Manyama_, May 11 2025 %Y A060056 A059419 (fourth column without zeros), A059420. %K A060056 nonn,easy %O A060056 0,2 %A A060056 _Wolfdieter Lang_, Mar 16 2001