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”).

A331251
Triangles with integer sides i <= j <= k sorted by area, and, in case of ties, lexicographically by side lengths (smallest first). The sequence gives shortest side i. The other sides are in A331252 and A331253.
11
1, 1, 1, 2, 1, 2, 1, 2, 2, 1, 1, 2, 2, 3, 1, 3, 3, 1, 2, 2, 1, 3, 1, 2, 3, 2, 1, 3, 2, 1, 3, 4, 2, 4, 1, 3, 2, 3, 1, 3, 4, 2, 4, 1, 2, 4, 1, 3, 3, 2, 3, 1, 2, 4, 1, 4, 4, 5, 2, 3, 4, 2, 1, 3, 3, 1, 2, 5, 4, 2, 1, 3, 4, 5, 1, 4, 2, 3, 3, 2, 4, 1, 5, 5, 3, 4, 1, 5
OFFSET
1,4
EXAMPLE
List of first triangles:
n
| 16*A^2
| | i .... (this sequence)
| | | j .. (A331252)
| | | | k (A331253)
| | | | |
1 3 1 1 1
2 15 1 2 2
3 35 1 3 3
4 48 2 2 2
5 63 1 4 4
6 63 2 2 3
7 99 1 5 5
8 128 2 3 3
9 135 2 3 4
10 143 1 6 6
11 195 1 7 7
CROSSREFS
Cf. A331252 (middle side j), A331253 (longest side k).
Sequence in context: A195969 A023518 A326194 * A309858 A375508 A022921
KEYWORD
nonn
AUTHOR
Hugo Pfoertner, Jan 19 2020
STATUS
approved