OFFSET
0,14
COMMENTS
The g.f. for "number of k's" is (1/2)*(x^k/(1+x^k))*(Product_{n>=1} 1 + x^n) - (1/2)*(x^k/(1-x^k))*(Product_{n>=1} 1 - x^n).
LINKS
Andrew Howroyd, Table of n, a(n) for n = 0..1000
FORMULA
EXAMPLE
a(13) = 2 because the partitions in question are: 7+6, 6+4+2+1.
MATHEMATICA
endpQ[n_]:=Module[{len=Length[n]}, EvenQ[len]&&len==Length[Union[n]]]; Table[ Count[Flatten[Select[IntegerPartitions[i], endpQ]], 6], {i, 0, 50}] (* Harvey P. Dale, Mar 03 2014 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Mircea Merca, Feb 20 2014
EXTENSIONS
Terms a(51) and beyond from Andrew Howroyd, Apr 29 2020
STATUS
approved