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.

A290809 One of the two successive approximations up to 7^n for the 7-adic integer sqrt(-5). These are the numbers congruent to 4 mod 7 (except for the initial 0).

Table of values

n a(n)
0 0
1 4
2 32
3 32
4 1404
5 13409
6 97444
7 215093
8 3509265
9 15038867
10 257160509
11 1669536754
12 5624190240
13 19465477441
14 310132508662
15 310132508662
16 28795501568320
17 228193084985926
18 1623976168909168
19 8137630560550964
20 76531001672789822
21 555284599458461828

List of values

[0, 4, 32, 32, 1404, 13409, 97444, 215093, 3509265, 15038867, 257160509, 1669536754, 5624190240, 19465477441, 310132508662, 310132508662, 28795501568320, 228193084985926, 1623976168909168, 8137630560550964, 76531001672789822, 555284599458461828]

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

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