A013293 - OEIS

%I #8 Dec 01 2013 11:26:18

%S 1,0,0,0,-3,40,-250,1008,-5887,56880,-263724,-1848000,36228093,

%T -377490984,7141572490,-132772794000,1495810787297,-10978685025568,

%U 115616765332680,-1113424428155904,-36631866029794659

%N E.g.f.: sech(log(x+1)-tanh(x))=1-3/4!*x^4+40/5!*x^5-250/6!*x^6+1008/7!*x^7...

%t With[{nn=30},CoefficientList[Series[Sech[Log[x+1]-Tanh[x]],{x,0,nn}],x] Range[0,nn]!] (* _Harvey P. Dale_, Dec 01 2013 *)

%K sign

%O 0,5

%A Patrick Demichel (patrick.demichel(AT)hp.com)

%E Definition clarified by _Harvey P. Dale_, Dec 01 2013