OFFSET
0,11
LINKS
Vladimir Kruchinin and D. V. Kruchinin, Composita and their properties, arXiv:1103.2582 [math.CO], 2011-2013.
FORMULA
R(n,k,m)=k*sum(i=0..n-k, sum(j=ceiling((i-m)/2)..i-m, binomial(j,i-m-j)*binomial(m+j-1,m-1))*binomial(2*(n-i)-k-1,n-i-1)/(n-i)), k>0.
R(n,0,m)=sum(j=ceiling((i-m)/2)..n-m, binomial(j,n-m-j)*binomial(m+j-1,m-1)), m=3.
EXAMPLE
0;
0,0;
0,0,0;
1,0,0,0;
3,1,0,0,0;
9,4,1,0,0,0;
22,14,5,1,0,0,0;
51,42,20,6,1,0,0,0;
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Vladimir Kruchinin, Feb 08 2011
STATUS
approved