login
This site is supported by donations to The OEIS Foundation.

 

Logo

Many excellent designs for a new banner were submitted. We will use the best of them in rotation.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A105200 Number of compositions of n such that the least part occurs with odd multiplicity. 2
1, 1, 4, 3, 13, 16, 41, 64, 154, 261, 560, 1049, 2176, 4169, 8474, 16614, 33477, 66178, 132776, 263969, 528519, 1053483, 2107772, 4207680, 8415341, 16812773, 33622527, 67203682, 134391649, 268686218, 537318189, 1074403625, 2148636672 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..33.

FORMULA

G.f.: Sum(Sum(binomial(k, 2*l-1)*x^(2*k-2*l+1)/((1-x)^(k-2*l+1)*(1-x^k)), l=1..floor((k+1)/2)), k=1..infinity).

MATHEMATICA

Rest[ CoefficientList[ Series[ Sum[ Binomial[k, 2l - 1] x^(2k - 2l + 1)/((1 - x)^(k - 2*l + 1)(1 - x^k)), {k, 34}, {l, Floor[(k + 1)/2]}], {x, 0, 34}], x]] (from Robert G. Wilson v, Apr 12 2005)

CROSSREFS

Cf. A096375.

Sequence in context: A120340 A082018 A056477 * A088933 A019136 A140884

Adjacent sequences:  A105197 A105198 A105199 * A105201 A105202 A105203

KEYWORD

easy,nonn

AUTHOR

Vladeta Jovovic, Apr 12 2005

EXTENSIONS

More terms from Robert G. Wilson v, Apr 12 2005

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Superseeker | Recent | More pages
The OEIS Community | Maintained by The OEIS Foundation Inc.

Content is available under The OEIS End-User License Agreement .

Last modified April 25 00:50 EDT 2014. Contains 240991 sequences.