cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A192712 Number of 11X2 integer matrices with each row summing to zero, row elements in nondecreasing order, rows in lexicographically nondecreasing order, and the sum of squares of the elements <= 2*n^2 (number of collections of 11 zero-sum 2-vectors with total modulus squared not more than 2*n^2, ignoring vector and component permutations).

Table of values

n a(n)
1 2
2 6
3 19
4 51
5 126
6 285
7 604
8 1208
9 2310
10 4237
11 7513
12 12885
13 21536
14 35072
15 55893
16 87271
17 133793
18 201572
19 299171
20 437546
21 631447
22 900231
23 1268643
24 1768448
25 2440754
26 3336495
27 4520239
28 6073339
29 8095214
30 10708816
31 14066591
32 18351402
33 23788458

List of values

[2, 6, 19, 51, 126, 285, 604, 1208, 2310, 4237, 7513, 12885, 21536, 35072, 55893, 87271, 133793, 201572, 299171, 437546, 631447, 900231, 1268643, 1768448, 2440754, 3336495, 4520239, 6073339, 8095214, 10708816, 14066591, 18351402, 23788458]

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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