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.

A240956 G.f.: Sum_{n>=0} n^n * x^n * (2 + n*x)^n / (1 + n*x)^(2*n+2).

Table of values

n a(n)
0 1
1 2
2 9
3 72
4 830
5 12420
6 228060
7 4959360
8 124589304
9 3550050000
10 113116311000
11 3985174226880
12 153815533185600
13 6454433029524480
14 292557975636326400
15 14244829479956275200
16 741502151945703308160
17 41092028680670274827520
18 2415394879269218890243200

List of values

[1, 2, 9, 72, 830, 12420, 228060, 4959360, 124589304, 3550050000, 113116311000, 3985174226880, 153815533185600, 6454433029524480, 292557975636326400, 14244829479956275200, 741502151945703308160, 41092028680670274827520, 2415394879269218890243200]