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A085282
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Expansion of (1-5*x+5*x^2)/((1-x)*(1-3*x)*(1-4*x)).
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3
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1, 3, 10, 35, 126, 463, 1730, 6555, 25126, 97223, 379050, 1486675, 5858126, 23166783, 91869970, 365088395, 1453179126, 5791193143, 23100202490, 92207099715, 368247268126, 1471245680303, 5879752544610, 23503319648635
(list; graph; refs; listen; history; internal format)
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OFFSET
| 0,2
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COMMENTS
| Binomial transform of A085281.
Number of walks of length 2n+1 between two adjacent vertices in the cycle graph C_12. - Herbert Kociemba (kociemba(AT)t-online.de), Jul 05 2004
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LINKS
| Vincenzo Librandi, Table of n, a(n) for n = 0..500
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FORMULA
| a(n)=4^n/3+3^n/2+1/6
a(n) = sum(binomial(2*n,n+6*k)/2, k=-floor(n/6)..floor(n/6)). [Mircea Merca, Jan 28 2012]
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PROG
| (MAGMA) [4^n/3+3^n/2+1/6: n in [0..35]]; // Vincenzo Librandi, May 29 2011
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CROSSREFS
| Sequence in context: A088218 A110556 A072266 * A149036 A047127 A114196
Adjacent sequences: A085279 A085280 A085281 * A085283 A085284 A085285
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KEYWORD
| easy,nonn
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AUTHOR
| Paul Barry (pbarry(AT)wit.ie), Jun 25 2003
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