sec(tan(tanh(x)))=1+1/2!*x^2+5/4!*x^4+13/6!*x^6+41/8!*x^8...
A012172
sec(tan(tanh(x)))=1+1/2!*x^2+5/4!*x^4+13/6!*x^6+41/8!*x^8...
Terms
- a(0) =1a(1) =1a(2) =5a(3) =13a(4) =41a(5) =1529a(6) =-168851a(7) =14151621a(8) =-1169749807a(9) =65719458673
External references
- oeis: A012172