Expansion of Product_{k>=1} ((1 - x)^k + x^k)/((1 - x)^k - x^k).

Terms

a(0) =1a(1) =2a(2) =6a(3) =18a(4) =52a(5) =146a(6) =402a(7) =1090a(8) =2916a(9) =7708a(10) =20160a(11) =52236a(12) =134222a(13) =342304a(14) =867024a(15) =2182384a(16) =5461696a(17) =13595918a(18) =33677550a(19) =83036878a(20) =203859820a(21) =498470998a(22) =1214230586a(23) =2947204870a(24) =7129403128a(25) =17191258642a(26) =41328057106a(27) =99067295658a(28) =236822823336a(29) =564650823162