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A221053
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The hyper-Wiener index of the nanostar dendrimer NSC_5C_6[n], defined pictorially in the A. R. Ashrafi et al. reference and in the M. Rostami et al. reference.
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2
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8580, 751148, 13742092, 145113196, 1166551916, 7991214060, 49348860396, 283593693164, 1546469947372, 8104770527212, 41179270758380, 204101468659692, 991328100589548, 4734560147021804, 22293506692030444, 103708270251417580, 477422926327128044
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OFFSET
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1,1
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COMMENTS
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a(2) has been checked by the direct computation of the Wiener index (using Maple).
The given references do not consider the hyper-Wiener index.
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LINKS
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FORMULA
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a(n) = 204780 - 1311272*2^n + 1106480*4^n + 360*2^n*n^2 + 129600*4^n*n^2 + 7852*2^n*n - 633600*4^n*n.
G.f.: 4*x*(1536*x^6-1645696*x^5-1592416*x^4+2192808*x^3-189320*x^2 -147032*x -2145) / ((x-1)*(2*x-1)^3*(4*x-1)^3). - Colin Barker, Apr 01 2013
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MAPLE
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a := proc(n) 204780-1311272*2^n+1106480*4^n+360*2^n*n^2+129600*4^n*n^2 +7852*2^n*n-633600*4^n*n end proc: seq(a(n), n = 1 .. 17);
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PROG
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(PARI) Vec(4*x*(1536*x^6-1645696*x^5-1592416*x^4+2192808*x^3-189320*x^2 -147032*x-2145)/((x-1)*(2*x-1)^3*(4*x-1)^3) + O(x^20)) \\ Colin Barker, Jun 04 2016
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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