|
Search: id:A127680
|
|
|
| A127680 |
|
a(0) = 1. a(n+1) = sum{k=0 to n} a(n-k)*a(floor(k/2)). |
|
+0
2
|
|
| 1, 1, 2, 4, 8, 17, 35, 74, 154, 324, 677, 1422, 2977, 6246, 13086, 27444, 57518, 120600, 252794, 529994, 1111013, 2329187, 4882755, 10236280, 21458943, 44986461, 94308415, 197707134, 414469000, 868886834, 1821517772, 3818600772
(list; graph; listen)
|
|
|
OFFSET
|
0,3
|
|
|
LINKS
|
Leroy Quet, Home Page (listed in lieu of email address)
|
|
MATHEMATICA
|
f[l_List] := Block[{n = Length[l] - 1}, Append[l, Sum[l[[n - k + 1]]*l[[Floor[k/2] + 1]], {k, 0, n}]]]; Nest[f, {1}, 33] (*Chandler*)
|
|
CROSSREFS
|
Cf. A127681.
Sequence in context: A018094 A001357 A058520 this_sequence A136750 A097107 A098083
Adjacent sequences: A127677 A127678 A127679 this_sequence A127681 A127682 A127683
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
Leroy Quet Jan 23 2007
|
|
EXTENSIONS
|
Extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), Feb 13 2007
|
|
|
Search completed in 0.002 seconds
|
