|
Search: id:A098156
|
|
|
| A098156 |
|
Interleave n+1 and 2n+1 and take binomial transform. |
|
+0
3
|
|
| 1, 2, 5, 13, 32, 76, 176, 400, 896, 1984, 4352, 9472, 20480, 44032, 94208, 200704, 425984, 901120, 1900544, 3997696, 8388608, 17563648, 36700160, 76546048, 159383552, 331350016, 687865856, 1426063360, 2952790016, 6106906624
(list; graph; listen)
|
|
|
OFFSET
|
0,2
|
|
|
COMMENT
|
Binomial transform of A029579.
|
|
FORMULA
|
G.f. : (1-2x+x^2+x^3)/(1-2x)^2; a(n)=0^n/2+sum{k=0..n, binomial(-1)^(n-k)*k)}/4+2^n/2+3n*2^(n-1)/4; a(n)=sum{j=0..n, sum{k=0..n, binomial(n, 2(k-j)}}.
a(n)=sum{k=0..n, sum{i=0..k, C(n, 2i)}} - Paul Barry (pbarry(AT)wit.ie), Jan 13 2005
|
|
CROSSREFS
|
Adjacent sequences: A098153 A098154 A098155 this_sequence A098157 A098158 A098159
Sequence in context: A095134 A086758 A116702 this_sequence A098586 A110320 A108890
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
Paul Barry (pbarry(AT)wit.ie), Aug 29 2004
|
|
|
Search completed in 0.002 seconds
|
