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%I #4 Jul 12 2013 13:39:21
%S 70159,5540677,94770993,962654441,7544225177,50760280441,309334151737,
%T 1759763688889,9520613312697,49581897574073,250630474019513,
%U 1236980426140345,5986802543205049,28507052162513593,133885149461756601
%N The hyper-Wiener index of the tetrathiafulvalene dendrimer defined pictorially as D[n] in the Shabani reference.
%D H. Shabani, Computing vertex PI index of tetrathiafulvalene dendrimers, Iranian J. Math. Chem., 1, 2010, 125-130.
%F a(n) = 1489593 + 2^n*(-190960*n^2 +743480*n - 13082162)+4^n*(3013696*n^2 - 7398832*n + 11662728).
%F G.f. =(70159 + 4207656*z + 21980*z^2 - 51514000*z^3 + 55017216*z^4 + 32361728*z^5 + 54272*z^6)/((1-z)*(1-2*z)^3*(1-4*z)^3).
%p a:= proc (n) options operator, arrow: 1489593+2^n*(-190960*n^2+743480*n-13082162)+4^n*(3013696*n^2-7398832*n+11662728) end proc: seq(a(n), n = 0 .. 14);
%Y Cf. A224463
%K nonn
%O 1,1
%A _Emeric Deutsch_, Jul 12 2013