%I A012830
%S A012830 1,4,88,4184,398848,58835456,12993783424,3911934210560,
%T A012830 1562951627091968,793328025614454784,501079933291827593216,
%U A012830 384338283691725654392832,352458553186266111883247616
%N A012830 arctanh(sec(x)*arcsinh(x))=x+4/3!*x^3+88/5!*x^5+4184/7!*x^7...
%Y A012830 Sequence in context: A028554 A154137 A154136 this_sequence A012946 A013101 
               A013067
%Y A012830 Adjacent sequences: A012827 A012828 A012829 this_sequence A012831 A012832 
               A012833
%K A012830 nonn
%O A012830 0,2
%A A012830 Patrick Demichel (dml(AT)hpfrcu03.france.hp.com)