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A159930
Triangle read by rows: a(1,1)=1. a(m,n) = a(m-1,n) + (sum of all terms in row m-1), for n<m. a(m,m) = sum of all terms in row m-1.
0
1, 2, 1, 5, 4, 3, 17, 16, 15, 12, 77, 76, 75, 72, 60, 437, 436, 435, 432, 420, 360, 2957, 2956, 2955, 2952, 2940, 2880, 2520, 23117, 23116, 23115, 23112, 23100, 23040, 22680, 20160, 204557, 204556, 204555, 204552, 204540, 204480, 204120, 201600
OFFSET
1,2
COMMENTS
The sum of all terms in row m is (m+1)!/2. So a(m,n) = a(m-1,n) + m!/2, or is m!/2 if n=m.
Sum of m-th row = A001710(m+1). [Klaus Brockhaus, Jun 02 2009]
First column is A014288. - Franklin T. Adams-Watters, Oct 19 2013
EXAMPLE
Triangle starts:
1;
2, 1;
5, 4, 3;
17, 16, 15, 12;
77, 76, 75, 72, 60;
PROG
(Magma) S:=[1]; T:=S; for m in [2..9] do s:=&+T; T:=[ n lt m select T[n]+s else s: n in [1..m] ]; S:=S cat T; end for; S; // Klaus Brockhaus, Jun 02 2009
CROSSREFS
Cf. A159927.
Sequence in context: A061579 A094064 A343809 * A058344 A010582 A266628
KEYWORD
nonn,tabl
AUTHOR
Leroy Quet, Apr 26 2009
EXTENSIONS
More terms from Klaus Brockhaus, Jun 02 2009
STATUS
approved