Numerators of coefficients in Taylor series expansion of (1+x+x^2)^(1/2).

Terms

a(0) =1a(1) =1a(2) =3a(3) =-3a(4) =3a(5) =15a(6) =-57a(7) =21a(8) =867a(9) =-1893a(10) =1581a(11) =8283a(12) =-76953a(13) =34203a(14) =361551a(15) =-869691a(16) =6420387a(17) =34130067a(18) =-167946159a(19) =79445631a(20) =1696170093a(21) =-4239570255a(22) =4083041217a(23) =21859150803a(24) =-442212416121a(25) =215805655695