Number of positive integers <= 2^n of form x^2 + 14 y^2.

Terms

a(0) =1a(1) =1a(2) =2a(3) =2a(4) =6a(5) =10a(6) =19a(7) =32a(8) =61a(9) =109a(10) =203a(11) =381a(12) =723a(13) =1371a(14) =2623a(15) =5040a(16) =9711a(17) =18781a(18) =36405a(19) =70710a(20) =137603a(21) =268242a(22) =523655a(23) =1023567a(24) =2002923a(25) =3923596a(26) =7693084a(27) =15097117a(28) =29649512a(29) =58271080