A060056 Nonzero numbers in expansion of ((tan(x))^4)/4! in (x^n)/n!.

1, 40, 2016, 135680, 11977856, 1351633920, 190346960896, 32769353973760, 6776471542235136, 1658320063181619200, 474140484461265944576, 156647023437347542794240, 59229231136268698009993216, 25414555567107834838389882880, 12283447443202253774326182445056

Offset: 0

Author

Wolfdieter Lang, Mar 16 2001

Keywords

• nonn
• easy

Crossrefs

A059419 (fourth column without zeros), A059420.

Programs

PARI

a059419(n, k) = n!*polcoef(tan(x+x*O(x^n))^k/k!, n);
a(n) = a059419(2*n+4, 4); \\ Seiichi Manyama, May 11 2025

Formula

a(n) = A059419(4+2*n,4).