Numerators of partial sums of a series for sqrt(2).

Terms

a(0) =3a(1) =11a(2) =23a(3) =179a(4) =365a(5) =1439a(6) =2911a(7) =46147a(8) =93009a(9) =369605a(10) =743409a(11) =5917879a(12) =11887761a(13) =47365319a(14) =95064943a(15) =3032383331a(16) =6082445497a(17) =24264959593a(18) =48649328861a(19) =388310999293a(20) =778263028691