A013054 - OEIS

%I #5 Sep 30 2025 20:34:17

%S 1,4,104,6598,778200,147293306,40870375036,15634022134518,

%T 7885949713950992,5071562424714844978,4050326064394675777988,

%U 3932747393021585152266894,4562459896809464230996563288

%N sec(sinh(x)+tan(x))=1+4/2!*x^2+104/4!*x^4+6598/6!*x^6+778200/8!*x^8...

%K nonn

%O 0,2

%A _Patrick Demichel_