Numerator of the Harary number for the path graph P_n.

Terms

a(0) =0a(1) =2a(2) =5a(3) =26a(4) =77a(5) =87a(6) =223a(7) =962a(8) =4609a(9) =4861a(10) =55991a(11) =58301a(12) =785633a(13) =811373a(14) =835397a(15) =3431678a(16) =29889983a(17) =30570663a(18) =197698279a(19) =201578155a(20) =41054655a(21) =13920029a(22) =325333835a(23) =990874363a(24) =25128807667a(25) =25472027467a(26) =232222818803a(27) =235091155703