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.

A260667 a(n) = (1/n^2) * Sum_{k=0..n-1} (2k+1)*S(k,n)^2, where S(k,x) denotes the polynomial Sum_{j=0..k} binomial(k,j)*binomial(x,j)*binomial(x+j,j).

Table of values

n a(n)
1 1
2 37
3 1737
4 102501
5 6979833
6 523680739
7 42129659113
8 3572184623653
9 315561396741609
10 28807571694394593
11 2701627814373536601
12 259121323945378645947
13 25330657454041707496017
14 2516984276442279642274311
15 253667099464270541534450025
16 25884030861250181046253181349
17 2670255662315910532447096232073

List of values

[1, 37, 1737, 102501, 6979833, 523680739, 42129659113, 3572184623653, 315561396741609, 28807571694394593, 2701627814373536601, 259121323945378645947, 25330657454041707496017, 2516984276442279642274311, 253667099464270541534450025, 25884030861250181046253181349, 2670255662315910532447096232073]