Logo

Greetings from The On-Line Encyclopedia of Integer Sequences!

Hints

Search: id:A117276
Displaying 1-1 of 1 results found. page 1
     Format: long | short | internal | text      Sort: relevance | references | number      Highlight: on | off
A117276 Number of 1's in all partitions of n with no even parts repeated. +0
2
0, 1, 2, 4, 7, 11, 17, 26, 38, 54, 76, 105, 143, 193, 257, 339, 444, 576, 742, 950, 1208, 1528, 1923, 2407, 2999, 3721, 4597, 5657, 6937, 8476, 10322, 12532, 15168, 18306, 22034, 26450, 31672, 37835, 45091, 53619, 63625, 75341, 89037, 105023, 123647 (list; graph; listen)
OFFSET

0,3

COMMENT

a(n)=Sum(k*A117274(n,k),k=0..n).

FORMULA

G.f.=x*product((1+x^(2j))/(1-x^(2j-1)), j=1..infinity)/(1-x).

EXAMPLE

a(5)=11 because the partitions of 5 with no even parts repeated are [5],[4,1],[3,2],[3,1,1],[2,1,1,1], and [1,1,1,1,1], and they have a total number 0+1+0+2+3+5=11 parts equal to 1.

MAPLE

g:=x*product((1+x^(2*j))/(1-x^(2*j-1)), j=1..35)/(1-x): gser:=series(g, x=0, 50): seq(coeff(gser, x, n), n=0..47);

CROSSREFS

Cf. A117274.

Sequence in context: A004250 A084842 A096967 this_sequence A035295 A006999 A005252

Adjacent sequences: A117273 A117274 A117275 this_sequence A117277 A117278 A117279

KEYWORD

nonn

AUTHOR

Emeric Deutsch (deutsch(AT)duke.poly.edu), Mar 06 2006

page 1

Search completed in 0.002 seconds

Lookup | Welcome | Find friends | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Transforms | Puzzles | Hot | Classics
More pages | Superseeker | Maintained by N. J. A. Sloane (njas@research.att.com)

Last modified November 18 20:14 EST 2008. Contains 147244 sequences.


AT&T Labs Research