Powers of sqrt(14) rounded up.

Terms

a(0) =1a(1) =4a(2) =14a(3) =53a(4) =196a(5) =734a(6) =2744a(7) =10268a(8) =38416a(9) =143740a(10) =537824a(11) =2012354a(12) =7529536a(13) =28172944a(14) =105413504a(15) =394421216a(16) =1475789056a(17) =5521897023a(18) =20661046784a(19) =77306558318a(20) =289254654976