0,2
Table of n, a(n) for n=0..7.
A013515 := proc(n)
sech(sec(x)-sech(x)) ;
coeftayl( %, x=0, 4*n) ;
%*(4*n)! ;
end proc: # R. J. Mathar, Dec 16 2011
Sequence in context: A271434 A160237 A013474 * A159383 A015011 A271435
Adjacent sequences: A013512 A013513 A013514 * A013516 A013517 A013518
sign
Patrick Demichel (patrick.demichel(AT)hp.com)
approved
