Series expansion for radius of gyration on honeycomb.

Terms

a(0) =0a(1) =0a(2) =144a(3) =2460a(4) =3168a(5) =32052a(6) =77976a(7) =420444a(8) =1310088a(9) =5655204a(10) =19291968a(11) =76066992a(12) =268063080a(13) =1011675420a(14) =3606884688a(15) =13288161216a(16) =47524261464a(17) =172579279812a(18) =616843377408