A331711 - cp's OEIS frontend

A331711 Number of nonnegative integer matrices with 2 columns and any number of distinct nonzero rows with column sums n and columns in nonincreasing lexicographic order.

n	a(n)
0	1
1	2
2	7
3	45
4	271
5	1244
6	7289
7	40841
8	201103
9	1044720
10	5172055
11	24532739
12	116470697
13	546142112
14	2505755203
15	11318525367
16	50046273319
17	219637249886
18	944072864849
19	4029243438335
20	16977344151163
21	70370874105726
22	289702060533067
23	1177283903981765
24	4740700176816041

[1, 2, 7, 45, 271, 1244, 7289, 40841, 201103, 1044720, 5172055, 24532739, 116470697, 546142112, 2505755203, 11318525367, 50046273319, 219637249886, 944072864849, 4029243438335, 16977344151163, 70370874105726, 289702060533067, 1177283903981765, 4740700176816041]

cp's OEIS Frontend

A331711 Number of nonnegative integer matrices with 2 columns and any number of distinct nonzero rows with column sums n and columns in nonincreasing lexicographic order.

Table of values

List of values