OFFSET
1,1
FORMULA
T(n,k) = (1/2)*(p(k)+p(2n+1-k)) for k=1,2,...,n, where p(1)=3, p(2)=5, ... are the odd primes.
EXAMPLE
First six rows:
4
7 6
10 9 9
13 12 12 12
17 17 15 15 15
22 21 19 20 18 18
Row 3 is formed from the first 6 odd primes:
3 5 7 11 13 17 --> (3+17)/2 (5+13)/2 (7+11)/2
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Clark Kimberling, Sep 08 2006
STATUS
approved