|
| |
|
|
A152120
|
|
A product sequence: a(n)=2^n*Product[2 + 3*Cos[k*Pi/n]^2, {k, 1, (n - 1)/2}].
|
|
0
| |
|
|
1, 2, 4, 22, 56, 290, 748, 3862, 9968, 51458, 132820, 685654, 1769768, 9136034, 23581372, 121733590, 314211296, 1622045954, 4186725796, 21613041046, 55786259480, 287984161058, 743327100556, 3837260885398, 9904503072464
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 0,2
|
|
|
FORMULA
| a(n)=2^n*Product[2 + 3*Cos[k*Pi/n]^2, {k, 1, (n - 1)/2}].
|
|
|
MATHEMATICA
| a = Table[2^n*Product[2 + 3*Cos[k*Pi/n]^2, {k, 1, (n - 1)/2}], {n, 0, 30}]; Round[%] FullSimplify[ExpandAll[a]]
|
|
|
CROSSREFS
| Sequence in context: A151809 A151801 A067654 * A072355 A134246 A071298
Adjacent sequences: A152117 A152118 A152119 * A152121 A152122 A152123
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Roger L. Bagula and Gary W. Adamson (rlbagulatftn(AT)yahoo.com), Nov 24 2008
|
| |
|
|
