|
| |
|
|
A107894
|
|
Sum over the products of factorials of parts in all partitions of n where the sum runs over the number of different parts only.
|
|
1
| |
|
|
1, 3, 9, 35, 167, 943, 6379, 48945, 429651, 4189865, 45307601, 535518109, 6883110373, 95435065935, 1420468921893, 22577620176887, 381695573051099, 6837601709298811, 129375694813679215, 2578070946813526485
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 0,2
|
|
|
EXAMPLE
| The partitions of 5 are 1+1+1+1+1, 1+1+1+2, 1+1+3, 1+2+2, 1+4, 2+3, 5, the corresponding products of factorials of parts are (when multiple parts are counted once only) 1!, 1!*2!, 1!*3!, 1!*2!, 1!*4!, 2!*3!, 5! and their sum is a(5) = 167.
|
|
|
MATHEMATICA
| Total[Times@@@(Union/@IntegerPartitions[#]!)]&/@Range[20] (* From Harvey P. Dale, Feb 26 2011 *)
|
|
|
CROSSREFS
| Cf. A077365, A107895.
Sequence in context: A097277 A034428 A101880 * A155858 A000834 A005346
Adjacent sequences: A107891 A107892 A107893 * A107895 A107896 A107897
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Thomas Wieder (wieder.thomas(AT)t-online.de), May 26 2005
|
| |
|
|
