OFFSET
0,2
LINKS
Reinhard Zumkeller, Rows n = 0..120 of triangle, flattened
FORMULA
Sum_{0<=k<=n} T(n,k) = A024528(n).
T(n+1,k) = prime(n+1) * T(n,k) for k=0..n and T(n+1,n+1) = T(n,0). - Reinhard Zumkeller, Nov 20 2015
EXAMPLE
Triangle begins
1;
2, 1;
6, 3, 2;
30, 15, 10, 6;
210, 105, 70, 42, 30;
PROG
(PARI) tabl(nn) = {for (n=0, nn, pr = prod(i=1, n, prime(i)); for (k=0, n, if (k==0, v = pr, v = pr/prime(k)); print1(v, ", "); ); print(); ); } \\ Michel Marcus, Apr 06 2015
(Haskell)
a121281 n k = a121281_tabl !! n !! k
a121281_row n = a121281_tabl !! n
a121281_tabl = [1] : f [1] a000040_list where
f xs@(x:_) (p:ps) = ys : f ys ps where ys = (map (* p) xs) ++ [x]
-- Reinhard Zumkeller, Nov 20 2015
CROSSREFS
KEYWORD
nonn,tabl
AUTHOR
Philippe Deléham, Aug 24 2006
EXTENSIONS
Corrected and extended by Michel Marcus, Apr 06 2015
STATUS
approved