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A009422 Expansion of log(1+x)*log(1+tan(x)). 1

%I

%S 0,0,2,-6,30,-160,1084,-8316,74456,-749184,8474240,-106035424,

%T 1459781056,-21914009728,356711937152,-6258266154752,117778607150592,

%U -2366994133647360,50601711980789760,-1146653711692951552

%N Expansion of log(1+x)*log(1+tan(x)).

%F a(n) ~ (n-1)! * (-1)^n * (4/Pi)^n * log(4/(4-Pi)). - _Vaclav Kotesovec_, Jan 23 2015

%t Log[ 1+x ]*Log[ 1+Tan[ x ] ]

%t CoefficientList[Series[Log[1 + x]*Log[1 + Tan[x]], {x, 0, 20}], x] * Range[0, 20]! (* _Vaclav Kotesovec_, Jan 23 2015 *)

%K sign,easy

%O 0,3

%A _R. H. Hardin_

%E Extended with signs by _Olivier GĂ©rard_, Mar 15 1997

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Last modified August 4 08:57 EDT 2021. Contains 346445 sequences. (Running on oeis4.)