a(n) = (A278399(n)^2 + A278400(n)^2)/2.

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =2a(5) =5a(6) =4a(7) =9a(8) =10a(9) =20a(10) =18a(11) =32a(12) =45a(13) =58a(14) =82a(15) =101a(16) =148a(17) =178a(18) =274a(19) =306a(20) =452a(21) =512a(22) =785a(23) =872a(24) =1258a(25) =1450a(26) =2061a(27) =2304a(28) =3274a(29) =3796