|
Search: id:A026165
|
|
|
| A026165 |
|
Number of (s(0), s(1), ..., s(n)) such that every s(i) is a nonnegative integer, s(0) = 2, |s(1) - s(0)| = 1, |s(i) - s(i-1)| <= 1 for i >= 2. Also sum of numbers in row n+1 of the array T in A026148. |
|
+0
1
|
|
| 1, 2, 6, 17, 49, 141, 407, 1177, 3411, 9904, 28808, 83931, 244895, 715534, 2093262, 6130767, 17974779, 52751358, 154950378, 455524203, 1340182539, 3945723033, 11624603235, 34268836707, 101081770181, 298320243976, 880875609552
(list; graph; listen)
|
|
|
OFFSET
|
0,2
|
|
|
FORMULA
|
a(n) = Sum_{k=0..n} binomial(n, k)*binomial(k+1, floor(k/2)). - Vladeta Jovovic (vladeta(AT)eunet.rs), Sep 18 2003
E.g.f.: exp(x)/x^2*((2*x^2-2*x)*BesselI(0, 2*x)+(2-x+2*x^2)*BesselI(1, 2*x)). - Vladeta Jovovic (vladeta(AT)eunet.rs), Sep 23 2003
|
|
CROSSREFS
|
Sequence in context: A052536 A122100 A122099 this_sequence A148445 A148446 A027914
Adjacent sequences: A026162 A026163 A026164 this_sequence A026166 A026167 A026168
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Clark Kimberling (ck6(AT)evansville.edu)
|
|
|
Search completed in 0.002 seconds
|
