A013467 -log(cos(x)-log(x+1))=1/2!*x^2+4/3!*x^3+7/4!*x^4+53/5!*x^5...

1, 4, 7, 53, 215, 1895, 12122, 132205, 1144627, 14912291, 164213696, 2477432371, 33228911417, 569758644845, 9014907260096, 173288317530505, 3159048447572983, 67337939660404735, 1389152842003647000