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A092080
Triangle read by rows in which row n lists the partition numbers of the first n positive integers.
3
1, 1, 2, 1, 2, 3, 1, 2, 3, 5, 1, 2, 3, 5, 7, 1, 2, 3, 5, 7, 11, 1, 2, 3, 5, 7, 11, 15, 1, 2, 3, 5, 7, 11, 15, 22, 1, 2, 3, 5, 7, 11, 15, 22, 30, 1, 2, 3, 5, 7, 11, 15, 22, 30, 42, 1, 2, 3, 5, 7, 11, 15, 22, 30, 42, 56, 1, 2, 3, 5, 7, 11, 15, 22, 30, 42, 56, 77, 1, 2, 3, 5, 7, 11, 15, 22, 30, 42
OFFSET
1,3
COMMENTS
Sequence of row lengths of array A092078.
Interpreted as a sequence a(n) = p(m) = A000041(m) (number of partitions of m) with m := n-L, where L is the largest number from A000217 (triangular numbers) which is less than n.
Row sums give A026905. - Omar E. Pol, Apr 23 2012
FORMULA
T(n,k) = A000041(k), k >= 1. - Omar E. Pol, Apr 23 2012
EXAMPLE
a(17)= p(2)= 2 because 17 = (15=A000217(5)) + 2.
a(10)= p(4)= 5 because 10 = (6=A000217(3)) + 4 (note that T < n, not <=n, is asked for).
Contribution from Omar E. Pol, Apr 24 2012 (Start):
Triangle begins:
1;
1, 2;
1, 2, 3;
1, 2, 3, 5;
1, 2, 3, 5, 7;
1, 2, 3, 5, 7, 11;
1, 2, 3, 5, 7, 11, 15;
1, 2, 3, 5, 7, 11, 15, 22;
1, 2, 3, 5, 7, 11, 15, 22, 30;
1, 2, 3, 5, 7, 11, 15, 22, 30, 42;
(End)
CROSSREFS
Cf. A000041.
Sequence in context: A066657 A119444 A060040 * A264482 A193588 A165884
KEYWORD
nonn,tabl,easy
AUTHOR
Wolfdieter Lang, Mar 19 2004
EXTENSIONS
Better definition from Omar E. Pol, Apr 24 2012
STATUS
approved