login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

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