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A210956
Triangle read by rows: T(n,k) = sum of all parts <= k in the last section of the set of partitions of n.
4
1, 1, 3, 2, 2, 5, 3, 7, 7, 11, 5, 7, 10, 10, 15, 7, 15, 21, 25, 25, 31, 11, 17, 23, 27, 32, 32, 39, 15, 31, 40, 52, 57, 63, 63, 71, 22, 36, 54, 62, 72, 78, 85, 85, 94, 30, 60, 78, 98, 113, 125, 132, 140, 140, 150, 42, 72, 102, 122, 142, 154, 168, 176, 185, 185, 196
OFFSET
1,3
COMMENTS
Row n lists the partial sums of row n of triangle A207383.
LINKS
FORMULA
T(n,k) = Sum_{j=1..k} A207383(n,j).
EXAMPLE
Triangle begins:
1;
1, 3;
2, 2, 5;
3, 7, 7, 11;
5, 7, 10, 10, 15;
7, 15, 21, 25, 25, 31;
11, 17, 23, 27, 32, 32, 39;
15, 31, 40, 52, 57, 63, 63, 71;
22, 36, 54, 62, 72, 78, 85, 85, 94;
PROG
(PARI) Row(n)={my(v=vector(n)); v[1]=numbpart(n-1); if(n>1, forpart(p=n, for(k=1, #p, v[p[k]]++), [2, n])); for(k=2, n, v[k]=v[k-1]+k*v[k]); v}
{ for(n=1, 10, print(Row(n))) }
CROSSREFS
Column 1 is A000041. Right border gives A138879.
Sequence in context: A151842 A076118 A309045 * A282161 A205675 A342331
KEYWORD
nonn,tabl
AUTHOR
Omar E. Pol, May 01 2012
EXTENSIONS
Terms a(46) and beyond from Andrew Howroyd, Feb 19 2020
STATUS
approved