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A000658
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Strehl's sequence "C_n^(3)".
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3
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1, 4, 68, 1732, 51076, 1657904, 57793316, 2117525792, 80483121028, 3147565679824, 125937573689968, 5133632426499152, 212530848994367524, 8914634034287235856, 378138515326996979168, 16196097181014298854032
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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REFERENCES
| Strehl, Volker; Binomial identities - combinatorial and algorithmic aspects. Trends in discrete mathematics. Discrete Math. 136 (1994), no. 1-3, 309-346.
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LINKS
| Reinhard Zumkeller, Table of n, a(n) for n = 0..100
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FORMULA
| Sum binomial(n, k)^2 * binomial(2k, k)^2 * binomial(2k, n-k); k=0..n.
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MATHEMATICA
| Table[Sum[Binomial[n, k]^2 Binomial[2k, k]^2 Binomial[2k, n-k], {k, 0, n}], {n, 0, 25}] (* From Harvey P. Dale, Oct 19 2011 *)
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CROSSREFS
| Third row of array A094424.
Sequence in context: A073774 A141032 A156084 * A156470 A009473 A009520
Adjacent sequences: A000655 A000656 A000657 * A000659 A000660 A000661
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KEYWORD
| nonn,easy,nice
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AUTHOR
| D. E. Knuth
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