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.

A378552 a(n) = Sum_{k=0..n} 9^k * binomial(n/3+k-1,k) * binomial(n-1,n-k).

Table of values

n a(n)
0 1
1 3
2 51
3 900
4 16455
5 307833
6 5850000
7 112445112
8 2180050215
9 42552000000
10 835075676361
11 16461248223588
12 325696500000000
13 6464447754891285
14 128654307202482420
15 2566472490000000000
16 51302899404879842343
17 1027391467409893403745
18 20607804108000000000000

List of values

[1, 3, 51, 900, 16455, 307833, 5850000, 112445112, 2180050215, 42552000000, 835075676361, 16461248223588, 325696500000000, 6464447754891285, 128654307202482420, 2566472490000000000, 51302899404879842343, 1027391467409893403745, 20607804108000000000000]

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

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