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A006859
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From paths in the plane.
(Formerly M5210)
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0
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1, 30, 330, 2145, 10010, 37128, 116280, 319770, 793155, 1808950, 3848130, 7719075, 14725620, 26898080, 47303520, 80454132, 132835365, 213578430, 335304970, 515175045, 776173134
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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REFERENCES
| G. Kreweras and H. Niederhausen, Solution of an enumerative problem connected with lattice paths, European J. Combin., 2 (1981), 55-60.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
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FORMULA
| G.f.: (1+x)(1 +19 x +56 x^2 +19 x^3 + x^4 ) / (1-x)^10.
a(n) = (n+1)*(n+2)^2*(n+3)^2*(n+4)*(2*n+3)*(2*n+5)*(2*n+7)/15120. - Peter Bala, Oct 11 2011
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CROSSREFS
| Sequence in context: A134287 A141216 A159543 * A107967 A115500 A125418
Adjacent sequences: A006856 A006857 A006858 * A006860 A006861 A006862
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KEYWORD
| nonn,easy
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AUTHOR
| Simon Plouffe (simon.plouffe(AT)gmail.com)
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