|
| |
| |
|
|
|
1, 10, 136, 2080, 32896, 524800, 8390656, 134225920, 2147516416, 34359869440, 549756338176, 8796095119360, 140737496743936, 2251799847239680, 36028797153181696, 576460752840294400, 9223372039002259456, 147573952598266347520, 2361183241469182345216
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 0,2
|
|
|
LINKS
| Vincenzo Librandi, Table of n, a(n) for n = 0..200
|
|
|
FORMULA
| With interpolated zeros 0, 1, 0, 10, ... has a(n)=(4^n-(-4)^n+2*2^n-2*(-2)^n)/16 and counts walks of length n between adjacent vertices of the 4-cube. G.f.: (1-10*x)/((1-4*x)*(1-16*x)); - Paul Barry (pbarry(AT)wit.ie), Mar 11 2004
a(n)= sum{k=0..n, 9*k*binomial(2n,2k)}= sum{k=0..n, 9^k*A086645(n,k)}; a(n)=8^n*T(n,5/4) where T is the Chebyshev polynomial of first kind ; e.g.f.: exp(10*x)*cosh(6*x) . [From Philippe DELEHAM (kolotoko(AT)wanadoo.fr), Sep 08 2009]
|
|
|
MAPLE
| seq(binomial(-4^n, 2), n=0..18); - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Feb 22 2008
|
|
|
PROG
| (MAGMA) [4^n*(4^n+1)/2: n in [0..30]]; // Vincenzo Librandi, May 01 2011
|
|
|
CROSSREFS
| Sequence in context: A128862 A129803 A065024 * A096619 A003377 A065593
Adjacent sequences: A026241 A026242 A026243 * A026245 A026246 A026247
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| N. J. A. Sloane (njas(AT)research.att.com).
|
| |
|
|
