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Numerator of [x^n] of the Taylor series arccosh(exp(x)-tanh(x))= x+x^2/2 -x^3/8 -7*x^4/48 +3*x^5/128 +631*x^6/11520 +37*x^7/15360 -12731*x^8/645120 -...

The e.g.f. at x/2 seems to admit an integer representation: arccosh(exp(x)-tanh(x)) = 2*x/(2*1!) +4*x^2/(2^2*2!) -6*x^3/(2^3*3!) -56*x^4/(2^4*4!) +90*x^5/(2^5*5!) +2524*x^6/(2^6*6!) ...