|
| |
|
|
A077047
|
|
Doubly restricted composition numbers: number of compositions of [n(n+2)/2] into exactly n positive integers each no more than n+1.
|
|
4
| |
|
|
1, 1, 3, 12, 85, 780, 9331, 134512, 2306025, 45433800, 1018872811, 25506741084, 707972099627, 21518492021208, 712601187601395, 25491847538274240, 981272544393935569, 40392787067756440272, 1772592132899627652691
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 0,3
|
|
|
LINKS
| Index entries for sequences related to compositions
|
|
|
FORMULA
| a(n) =A077042(n+1, n).
|
|
|
EXAMPLE
| a(3)=12 since the compositions of [3*5/2]=7 into exactly 3 positive integers each no more than 4 are: 1+2+4, 1+3+3, 1+4+2, 2+1+4, 2+2+3, 2+3+2, 2+4+1, 3+1+3, 3+2+2, 3+3+2, 4+1+2, 4+2+1.
|
|
|
CROSSREFS
| Cf. A077042, A077045, A077046, A077048.
Sequence in context: A147835 A032183 A070825 * A074505 A039305 A174463
Adjacent sequences: A077044 A077045 A077046 * A077048 A077049 A077050
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Henry Bottomley (se16(AT)btinternet.com), Oct 22 2002
|
| |
|
|
