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A015212
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Sum of Gaussian binomial coefficients for q=21.
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1
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1, 2, 24, 928, 224096, 180925632, 915592324864, 15519120649837568, 1649093881865807133696, 586980815917441872922703872, 1309843539264798142345101012967424, 9790772765676733007363874643686313525248
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OFFSET
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0,2
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REFERENCES
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J. Goldman and G.-C. Rota, The number of subspaces of a vector space, pp. 75-83 of W. T. Tutte, editor, Recent Progress in Combinatorics. Academic Press, NY, 1969.
I. P. Goulden and D. M. Jackson, Combinatorial Enumeration. Wiley, NY, 1983, p. 99.
M. Sved, Gaussians and binomials, Ars. Combinatoria, 17A (1984), 325-351.
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LINKS
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FORMULA
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a(0) = 1, a(1) = 2, a(n) = 2*a(n-1) + a(n-2)*((21^(n-1)) - 1). - Vincenzo Librandi, Nov 02 2012
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MATHEMATICA
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Total/@Table[QBinomial[n, m, 21], {n, 0, 20}, {m, 0, n}] (* Vincenzo Librandi, Nov 02 2012 *)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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